1. Buy only enough paint to do the job

Recent studies have shown that between 10% to 15% of paint bought by householders remained unused at the end of a paint job.

2. You don’t have to wash your brushes out between applications.

water-based paints:
store brushes and rollers in plastic bags between coats

solvent-based paints:

store brushes and rollers underwater and when ready to re-use, roll or brush water out on scrap newspaper which can be put out with your household waste