Do you have assigned standard colours in your house?

We don't do this. We just use whatever towels are there and any mug is available to anyone. That said, we all tend to opt for certain mugs but this wasn't a specific rule, it's just the way it works. We should, however, have this for socks. We all wear black socks, so we have yo be really careful, at least when we dry them. We all do our own washing so nothing gets mixed up in the wash, but it the drying that is when the risk of mix ups can happen. If things go smoothly then my sons washing is dried before I put my socks up to dry, and I make sure to remove them before my hubby does his washing - although he tends to tumble his socks so this does lessen the chance.