You just catch it in the palm of your right hand, as you jab back. If you pivot to your left as you catch and jab your punch will generally get there before his. You can work a few other things off of this.
Once you catch that jab, if you stay in front of him, he'll know you are in range and throw a right hand. That opens up opportunities for you to counter. Or you can catch that jab a time or two, to get him stepping hard with it, then parry and bring that jab up like we talked about earlier. (To parry, just slap it aside with your right glove. Let it get real close to you, push it aside as you jab or hook back.)
You can message me here, as I'm on most everyday, and I'll be glad to answer any questions you may have, if I know the answer.