The things I have learned:
- Frog Tape works much better than blue Painters tape.
- Check the mis-mixed paint shelves in your local paint departments. Menards has gallons for $5, Lowes charges $9. I also got some from the Habitat for Humanity Restore Shop for $2-3/quart. These were good colors, so I was happy to pay that.
- Transfer some of the paint into a plastic throwaway container. Since you need 3-4 coats, it's much easier to get in to than a paint can.