Lutz1873:
What's the quickest/most efficient way of building credits.
Search the forums and you will find discussions of various topics - including this one.
As to credits, you can:
1. buy them
2. get them by watching "free credit" videos on mobile
3. place in tournaments that have a purse.
Quickest is #1, most efficient (cost-wise) is #2, most fun is #3.
Key thing is to stock up on them and only upgrade a club or ball when you have come close to mastering the one you are playing.