Just wanted to share this quick little tip that I found at Martha Stewart.com - http://www.marthastewart.com/275689/good-things-for-painting/@center/276988/painting-ideas-and-projects#/180400.
I used this a couple of weeks ago when painting the master bedroom. This is a project that I have been working on for some time now. Basically painting a little at a time when O would go down for a nap.
Instead of pouring my paint directly into the paint pan, I lined the pan first with foil and then pour in my paint. When I was finished, I just threw the foil away and for the most part had a very clean paint pan. There was a little paint on the lip of the pan, but much easier to rinse then the entire pan.
I encourage you to check out the link above before your next painting project. She lists a total of 9 painting tips. Happy Painting!