the stuff you go to buy just look at the info about it. most the stuff you start out with will be level 1 & don't really help you much. once you start getting sponsors you unlock more stuff & then you'll start to see stuff you can buy that will have level 3 or 4 with little green boxes that increase the skills you do have.
most the time with the training on challenges and stuff they want you to get pretty close to the pin. try different clubs & what not to try and get there. just remember how many clicks (how many times you push the control pad a certain way) & if you do good on it do the exact same thing again.
if you are playing by yourself do the tiger challenges when you do good on those you get skill points that later on after that match you should be able to use in the next one. under "my career" look in "my skills".
hopefully that helped out some. i just recently got the game not too long ago & have been playing a lot. so if you have any other questions just message me, i might be able to help since the book that came with the game is seriously lacking.