Starting with the basics IMO is all about composition and one of the hardest things for beginners to do is "tight composition", we see the world from birth as a panarama. EG
Pic 1 We do not need to know it is taken in a skate park, the subject is the skater, the rest we can imagine. Crop in tight to the subject so that you lose the pole and most of the ramp at the back and crop down almost to his helmet.
Pic 2 Crop even tighter
Pic 4 How about him, skate board and sky - nothing else