Give Some Tips

Play longer time controls, at least until you are familar with more lines, and positions. You can also practice lines on a board, and blitz can help memorize them. However if you are having problems at current time controls, you need to increase the time controls. I couldn't pick up pieces, and move them quickly enough, especially on a computer. Also mouse slips, mis clicks, etc. Definitely doesn't help. So in other words it may be a number of reasons/problems that need to be resolved.