Can you post a couple more photos, one or two of them looking towards the house too?

And which way does your garden face?

it's south-east facing

Here's an idea for you:
- a large patio, decking with Taxus baccata hedges on the sides (poisonous, don't eat it). Taxus is evergreen and doesn't require lots of pruning. The decking will be a natural step down into the next part. Square borders (lavender?) mark the end of the deck. - gravelled area with pavers. Space for a bench.
- flowering perennials under a trellis screen, or just square wooden poles small distances apart, to hide the shed and bins.
- two small trees (look at Pyrus Calleryana 'Chantecleer') to give height, privacy and some much needed shade in the summer (I guess/hope)

The most obvious and positive thing is that you can use the slope to create at least two levels, with however many steps are needed in between. If you also add some raised beds then you have a lot of interest from the structure. A few taller plants or trees will create more of an enclosed feeling them but you need to carefully consider their placing as you may want to retain the sun.

If you want/need to do the work yourself then timber is probably the best bet, as long as it is treated. If you have more budget them rendered blockwork will last longer.

As you don't want real grass, you could look into AstroTurf which had come on in leaps and bounds. We have some in the front of our basement flat just to brighten the area up; we are quite pleased with it and have had several compliments from the neighbours

HI Ive heard of fake grass assuming it is like astro turf so quite put off! However whilst in local Jewsons I had the chance to see it close up and omg how amazing is it? Its even got bits of brown within so its v realistic, soft and nothing like astro turf!! So even a large circle surrounded by low maintenance beds would be softer than hard landscaping and no mowing!!

The key is to mask the boundaries (and the shed) and lead the eye and the visitor through the garden in the most indirect way possible. You can achieve this by utilising the change in levels, either via one step of a generous patio or decked area or a series of shallow steps; creating screens with planting or more physical screens structures such as trellis that obscure the whole garden from view from the house to encourage you to explore; create focal points that distract your eye from the boundaries and lead you through the garden; use height in the garden with planting, structures such as pergolas and archways; and use trickery such as mirrors, false doors to create the illusion of a larger garden beyond. Other factors worth considering are sticking to a limited palette of materials (including plants) to avoid a haphazard approach, use a few large pots rather than lots of little pots that look hectic and require more watering, keep areas for seating and paths generous so they don't feel mean and restrictive and consider lighting for use after dark or just enjoying the house from the garden at night. Perhaps a generous paved area by the house stepping down to a central gravelled area with Mediterranean style planting planted within it in a loose circular shape, a slatted timber screen with planting in front of the shed and an archway leading through to a utility area next to the shed which is out of view of the rest of the garden. I'd stick to just one specimen tree in front of the shed that could be uplit at night using a species that has dual interest with spring flowers and autumn leaf colour. Overall enjoy experimenting, have fun!

I agree with annarocks123. Walking round the area with my little dog I've noticed that a few people have had fake grass (I know because they told me it was fake) and if you don't get the very cheap stuff it can look quite impressive.

Bamboo is a nightmare. Don't plant it. It's invasive. Draw out to scale and then decide on seating area and any pathways. Screen the shed. Then decide if grass decking or paving . Could be low maintence without grass and use lots of tubs. You will need a focal point. Maybe a sculpture. Lighting is a must

raised sleeper beds with bamboo could work to shield the bottom

This is great, lots of ideas to explore: thank you!

Depends on where you live as to what is right colourwise with hard landscaping, but considering house style/colour and that of neighbours, would suggest slate terrace directly across the back of the house, at least 3m, Then down a step or two to lower area and edge same slate tiles creating a border at least 1m wide for planting against the fencing, infilled with stones (i.e.. larger than gravel!). A few large planters with exotic looking plants (Fatsia, bamboo - black or golden would look good, canna in summer - ask your local garden centre for advice). After planting the borders with plants to scramble over the fences, like self clinging vines, ivy etc, put gravel over borders on top of weed suppressing fabric. Paint the fencing light grey, the shed dark grey or perhaps white to contrast. Or go wild with a whizz of colour?!

if you want to get on with your neighbours I'd avoid pleached trees round the boundary, you'll be blocking their sunshine and light.

...and don't forget to include a place for a bird table (Christmas present?)

You could paint the shed harmonious pastel colours in stripes, along the shingles, so it looks like a beach hut - maybe shades of green and pink to go with the green mineral felt roof. Then grow shades of pink hollyhocks in front of it.

Also you could roughly paint the fence with thin white paint and a dryish brush so it looks lime-washed

We had our garden redesigned this summer and love it. If your budget will permit, it's certainly worth engaging someone to draw up a plan and do the hard work for you. Our garden design came from our own ideas - round lawn and square pond were our starting point - and between us and the designer we now have a very lovely outdoor space where we spend most of our time. Blankets allow us to sit outside until after dark and only rain keeps us indoors! (The photo doesn't show the patio where we spend our time.)
Angie

I forgot to say our garden slopes downwards away from the house, although we hadn't realised until the designer pointed it out! He was very particular about getting the levels right. You could try a sloping path to lead from one area to the other. And having something in the middle of the garden, such as trellis helps give the feeling of space somehow. Not sure how but it does!
Angie

I would be inclined to introduce some circular aspects to this garden. I understand you wishing to not own a lawn mower (a small lawn can sometimes prove to be more hassle than it's worth!).

Others have suggested artificial grass: a small circular artificial lawn will be great if you have children as it provides a fairly soft and mud-free space to play on!

Raised beds are great, however it's always worth first analysing whether you have a need for them (i.e. to keep dogs away from plants) - otherwise the money and labour could be better spent on plants and other materials. The space you have is fairly small, so adding too many materials could make the space feel fairly enclosed. Large beds full of low maintenance perennials, grasses and shrubs will give you the best use of this space, perhaps surrounding a circular patio. The reason I am suggesting the use of circles, is that it will enable you to have beds of varying sizes which will help to create the illusion of a larger space.

If you would like any further advice or if you are based locally to Hampshire and would like a team to implement your ideas - we'd be more than happy to help.

we have bamboo in our garden had it for 4 years, when first planted we left it in its large pots and slit the sides then planted the bamboo in its pots in the ground,had no problem with it straying into the rest of the garden, it sounds nice when there is a bit of a breeze and you can let it grow to any height as its easy to trim i have it along my fence with other lower flowering shrubs in front for colour in the spring and summer,my garden just started out with borders then i kept adding stuff over the years, i have to have flag and decking as i use a wheelchair,hence the ramp my brother made the raised wood planters to make it easier for me to potter on.

the other side of my garden is also flagged with boarders and a small shed its south facing,as is yours so you should be able to grow almost anything,i have plants in that come back every year to make it easy, ( fuchsias. butterfly bushes, lilies,lavender,roses,} in the winter they just get cut down then they all bounce back up again in spring and summer,this garden was just 2 lawns when i moved in and not a plant in sight now its full of colour

vlv mcc - what a lovely garden. And it seems exactly what Arianne wants too! Such great satisfaction in creating one's own space so well.

Hi i am happy you like my little garden retreat, you are right it is nice to add your own touch to your garden and not to be to regimental, it gives you a great satisfaction when you sit back in your garden lounger and think i created that, it also works out a lot cheaper, just adding bits at a time, and if a plant is not working for you, you can dig it out and move it knowing that you have not paid someone a fortune to put them in, i am not saying professional help is not needed as i had to get someone in to do my flag stones but it was someone i knew so that worked out cheaper and my brother did the decking at both side of my garden, he is not a professional he just likes DIY don't tell him but i think he is pretty good at it lol.. it cost me the price of the wood and 2 cans of beer,( i was given a couple or quotes of £450 for a 10ft x 7ft deck and £399 for a 7ft x 6ft deck,) i did paint it big mistake on my part as with being south facing it just peeled off with the heat but is nearly all off now so i will just power wash it once a year and give it an oil treatment, when you get your garden done send us a pic i for one would love to see your project,

Try a gas fire pit from Elementi fires

a large range of fire pits to suit any garden

sociable and very cosy

Steve