Whether you have a small home and struggle for space or if you have a larger home, but still have lots of stuff to organise, one thing you might want to explore is whether you are using every space, no matter how small, as effectively as you can. Even the smallest nooks and crannies can be redesigned so that they provide you with some really useful storage.
One area that we have managed to use that most people perhaps wouldn't think to use is the space above a door. Our downstairs toilet is a really tiny room and with little space to have any storage to keep cleaning products and toilet rolls etc.
So we created a wide shelf that sits above the door and stores everything we would like to keep in there. We don't really notice it's there unless we actually need to get something down and it's just such a handy way to make use of what would otherwise be dead space. It also means we don't need to put any cupboards on the wall or take up any floor space, which would make the room seem even smaller.
Other places around the home that you might be able to make similar use could be in the large space above the stairs - I've seen some people line the edges with bookshelves as a book storage area. Also, under the stairs can be utilised better by putting built in drawers for shoe storage, hoovers and anything else that might not have an obvious home elsewhere!