I don't believe you should potty-train your child while wearing diapers. In fact, I don't think you should expose your fetish to your child at all. I don't think you should let them see the diapers you keep in your room (or wherever), and I especially don't think you should visibly wear diapers around the child.
I just think that a kink is best kept to oneself and one's partner. Friends don't need to know, relatives don't need to know, and one's children don't need to know, either.
Angelabauer makes a good point in that her family is mostly incontinent, yet she and her sister were still potty-trained. So wearing diapers around the child probably won't interfere with his potty-training.
Also, think about this: If your child knows you wear diapers, and your other contacts (relatives or friends) don't... What happens when your child says something like, "Daddy wears diapers"? Kids aren't very discreet.
Best of luck to potty-training your kid.