the way i improved was through playing maps i couldn't pass before and aiming to get b's or c's on them. also, i heard that omgforz's method was to play maps that are fc-able or a-able with a few misses. i think either way, as long as you keep playing, will help you become a better player. additionally, you shouldn't limit yourself to only nomod; putting mods on could help with speed, accuracy, and aim (reading if you decide to try ez mod) as well. be persistent, play for fun, don't get frustrated if you can't do something.