The Toyota paints now let you choose between brush and pen method. I use the pen, as it's like the toothpick method that kris mentioned. If your only choice of applicator with the paint you buy is a brush, use a toothpick instead of the brush.

I've had good results with the pen applicator on a Toyota OEM tube of paint.

"When you get to the fork in the road, take it." --Yogi Berra