Can we talk frugal make up tips?

I can't be the only frugal make up user here, and beauty products can be soooo expensive! Here's my tip: I've had my liquid eyeliner for over a year. Whenever it starts to dry out, I add a few drops of water and then let it soak in a container of really hot water for a while to make sure it mixes. Then just shake it up a lot. This has saved me from throwing it away at least 3 times!

What are your frugal make up tips?