Replying to Framing tips/questions

Yo! So I'm just starting to finally crack into doing some filming and I was looking for a bit of guidance in terms of perfecting follow cams, and any tricks/setups that work best. These are some pretty beginner questions honestly.

I'm having lots of trouble keeping whoever is riding in frame throughout the shot, especially on jumps. Usually I get the run in and the take off perfectly but then they fall out the bottom as they go through the jump. Similarly, in follow cams I have a lot of trouble keeping the rider well framed through the whole shot.

-Is getting good at this something that just comes with time? Should I be trying to look at my LCD while doing follow cams or do I just have to keep doing it and the framing will come naturally with time.
- would something like a shoulder rig help, and maybe even slapping on one of those viewfinder adapters so I can actually see the screen? Have you guys ever tried one of those?

For reference I'm currently using a home made PVC fig rig until I can save up for a glidecam. I also have a tripod of course.

Cheers!