One of the best ways I've found to keep things tidy is to just put things away as you go. Once I get home from work or college, I know I'll be dead to the world as soon as I sit down, so I don't let myself sit down until I've spent a couple minutes putting things away. I hang my coat up, put my shoes where they belong, hang my purse up/put my backpack away, take anything out of them that needs dealing with, put my phone on my desk, and maybe take care of a couple extra little things while I'm at it (like throwing out soda cans on my desk, putting dirty cups in the sink, etc.). That alone is really good at stemming the tide of mess. Once I've done that, I can just crash for a while and have a tidier area to do it in, too.