I would go very modern and clean, you don't have to spend a lot of money. Painting the walls white would be a cheap and easy way to brighten the space. The add personality with accessories, art work and bedlinen. Have a look at our Ikea hacks https://www.thedesignerandthedecorator.co.uk/journal/diy-furniture Ikea Rast chest of drawers could make nice bedsides. Also for wardrobe, You could install an open hanging system from ikea like the photo below Or with a little bit of budget Sharps wardrobes could make a custom wardrobe around the bed And a lift up storage bed also helps with a small space

Thank you all for your help so far! What colour do you think the bigger rug should be? I was looking at things like this https://www.houzz.co.uk/products/metro-rug-black-and-white-60x90-cm-prvw-vr~116921750 https://www.houzz.co.uk/products/jersey-8420-rug-stone-140x200-cm-prvw-vr~112201633 https://www.houzz.co.uk/products/copperfield-rug-60x90-cm-prvw-vr~116921735 but is it too much of the same colour for the room?

Thank you. Is this tile suitable for small shower room? https://www.tiles-direct.com/floor-tiles-c27/heritage-parquet-c2171/cedar-grey-parquet-wood-effect-60cm-x-60cm-floor-tile-p5036

If budget is tight then just putting internal doors on is a great idea….. you can buy wardrobe doors in the same way and this might be better as they will be narrower. Assuming the bedroom space is the same size I might swap the two spaces so that dressing room is on the way out and an early riser doesn’t disturb someone still sleeping. If the bedroom is significantly bigger then I would put a chair in there- in the dressing room it will become a clothes horse and never be sat on. And so here is what I would do including an extra side window