My husband LOVES to make fun of me for this - but whenever I paint or work on a particularly messy project - I wear my clothes inside out.
It is easier that keeping track of what are project clothes and what isn't, or risking ruining something that I really like. It doesn't work too well with jeans obviously, but I have 3 favorite pairs of capri sweatpants that I live in on weekends. Pretty much year round. They are perfect. So when I want to work on a project, I just wear them inside out and I never have to worry about ruining them.