Well, obviously for you to get better at basketball you need to play more often
I'm only fifteen, but i practice about 8 hours on school weeks and during the summer 3 hours a day, so i might now a bit about basketball
To develop a quicker shot, always, always keep your arms up, i have seen many player catch the ball high and instead of immediately releasing from above the waistline, they bring the ball down below the waistline and then shoot
First of all this doesn't increase your range and it slows your shot down
You might not think you do this, but many players do this naturally and feel like they dont do it
I used to shoot like that , until i videotaped my shooting style and tried to create a faster shot for myself
If you want a faster shot off the dribble, i prefer dribbling up with the weaker hand, it gives you a better grip and faster movement to get in shooting position