One of the first things you'll need to decide is when you are thinking of moving. If you are looking to move in the immediate future, your focus will be on making aesthetic improvements to make your home more 'sellable'. Alternatively, if a move is a year or more away you could benefit from taking on a more significant project to add value to your home.
In my late teens I was keen to get out of my mum's house ASAP, which meant spending several years living in dingy basement flats and warehouses with no hot water. At times it was a bit grim but it's all part of growing up and it taught me a lot. For me - now I'm living somewhere less squatter-chic - I've learnt to create an illusion of space.