So me and a friend picked up SSF4:AE a few days ago (whenever the Steam sale was on), and we've been having a blast. Although I'm terrible and can't do any combos other than the most basic cancels (outside of training mode anyway), I feel as though I'm making steady progress. Anywho, I'm looking for advice on how I'm supposed to counter jumping. My friend jumps CONSTANTLY. I've read that jumping is supposedly bad since it so easily punished (whenever I attempt to imitate his strategy it always goes horribly awry), however I don't really know what I'm supposed to do to punish it. He also does crossups (I think that that's the word for jumping over me, and landing on the other side) ALL THE TIME. I mainly play charge characters so this always messes up my "charging." I mainly play Guille and Dee Jay (I know that he's low tier, I just really enjoy playing him). Also, any other tips on how to play against Juri (his main) would be appreciated. Thanks.
Tl;Dr: What should I be doing to counter crossups and jump ins?
Tl;Dr: What should I be doing to counter crossups and jump ins?