With a small brush, apply the paint around trim and corners of walls where your larger brush or roller can't reach.
Try using a "W" pattern to paint walls. Start in the corner of a wall and roll on a three-by-three foot "W" and then fill it without lifting the roller. Repeat until the section is finished. This helps hide any seams and any places where the roller has been lifted and put back on the wall again.
The same color of paint can vary between cans. To ensure color consistency from start to finish, the pros mix their cans of paint in a 5 gallon bucket, a process called "boxing".
Wash your roller covers! Washing them before their first use gets rid of the fuzz that comes off once you start painting. Wash with water and a little bit of liquid soap and run your hands over the covers to pull off any loose fibers. You can start using the roller covers right away – no need to let them dry!