How can I improve my basketball technique?

I play once a week, and would like to improve in comparison to the guys I play with/against, basically so that I don't get picked among the last. All of us are amatuers, but most seem better than me, at least they score as much or more.

I know practice makes perfect, but I only play once a week and rarely manage to squeeze in another session. At this level I wonder if perhaps I can improve merely by incorporating some drills/techniques as opposed to most people just coming in and playing like they always do.

I feel I have already improved quite a bit by learning the correct way to shoot from standstill, and some dribble and ball control techniques.

However I still feel lacking in ball control, and penetration. For example I can do an unguarded lay-up naturally from the left, but no matter how much I practice it still feels wobbly from the right. Penetrating against defence I usually manage a shot but miss too often.

Any tips and suggestions would be appreciated.