Watch the Forward Reverse Roll online guitar lesson by Ben Wright from Bluegrass Banjo for Guitar Players
The basic metronome exercise with the forward reverse roll. As a side note, watch that your finger picks aren't too tight on your fingers. They should grip firmly, but not cut off circulation and hurt to take off. Believe it or not, your fingers change size during the day due to hydration and other factors. Be sure to adjust the metal picks as need be.