How to train my older horse?

I have a 10 yr old POA gelding (13.3 hh) that I recently bought from a family friend. He has great ground manners, he's had a blanket on him and today I put a saddle on him (didn't cinch it up). He's a very easy going horse and I put some weight on his back and he didn't care at all. But I have no idea what to do next! Haha I want him to be my western mount and he'd be GREAT! But I just need to train him. Any tips help!!