Whether you buy cheap or expensive roller covers, washing them before their first use gets rid of the fuzz that inevitably comes off once you start painting. Wash them with water and a little bit of liquid soap, and run your hands up and down the covers to pull off any loose fibers (a practice called "preconditioning covers"). You can start using the roller covers right away—you don't need to let them dry.
Ideally, you want as much paint on the brush as you can control without making drips or blobs. To do this, Doherty dips his brush about 1 1/2 inches into the paint, then taps (not wipes) each side of the brush against the side of the can. Tapping knocks off the drips and forces the paint into the bristles. "The brush releases the paint just like a fountain pen," he says. Weeks agrees, saying, "Just be sure to keep your brush moving, or it'll start to drip." For more delicate work, such as when you're painting trim or window sash, you'll want less paint on the brush. Doherty again dips and taps his brush, but this time he also scrapes the sides against his can. "The outside bristles are drier and easier to manage," he says, "but there's still plenty of paint on the brush."
Most pros don't bother cleaning brushes and rollers if they are going to use them the next day on the same job. "Latex paint dries slowly in cold temperatures," says Maceyunas. For two-day jobs, he wraps the rollers and brushes in plastic grocery bags and sticks them in the refrigerator. "Just allow the roller to return to room temperature before reusing it," he says. Roller covers are almost impossible to clean thoroughly. Most pros buy new covers for each job.