Well as said before practice make perfect..:
To improve in:
Ball Handling-Do lots of dribbling drills until your hand can dribble very fluently
Court Vision-Well this is really the hardest part to see well in the court you would need to think and decide becos in the end your decision will produce the outcome of the results you know what Im sayin its really like good decision=good result which mean you score,etc..
Defence-Well practice with someone and try to D him, in the beginning take someone who is easy then progress yourself..
Offence-Ah well dont evryone want to score offense is just like D take someone who would guard you, like in D start with someone who is easy then progress your way up..
Pressure/Nerve-Well play in many bball games and you will get use to the pressure/nerves..

I hope that helped..

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