Next time you're painting a room and want to take a lunch break—or even knock off for the night—don't bother rinsing out the roller sleeve. Instead, roll out as much of the excess paint as possible, then cover the roller sleeve in aluminum foil. Crimp the foil around the ends of the sleeve to seal out air.
If you're not going to be able to get back to painting for more than 12 hours or so, pull the sleeve off the roller frame and pop it into the refrigerator. There, it will stay fresh for up to four days. Take it out of the refrigerator—but don't unwrap it—at least two hours before you're ready to resume painting. This warm-up period allows the nap to become pliable again and ready for painting.