How do I maintain my oil paint brushes?
When I'm done painting, this is how I clean up. I've kept some brushes for years like this:


Soak the brush in white spirit for a minute or so
Gently massage the bristles to loosen the paint and make sure as much as possible is dissolved in the spirits
Put a good dollop of liquid soap onto the bristles, and gently scrub into a lather with a bit of warm water (not hot), separating the bristles to get as much paint out as possible
Rinse out with warm water
Repeat if necessary


Make sure the flow of water is always from handle to tip, make sure you're never pushing paint up towards the handle as it can collect there where it's almost impossible to get out, and it will harden and splay the bristles over time.