If you goto a gym, they should have a chin/dip assist machine (it's pretty tall). If your gym doesn't have one of those, it should have dip machine (same motion, but you just add the weights instead of lowering the resistance.)
I may not be doing it right, but I am gonna wait until I get to the 10's to add in dips. If I do fifteen now, i would hit failure. I am gonna add dips and hang weight from my waist. It may not be the right thang to do, but that is what I decided.
unfortunately, I don't think I can do even 10 pullups
Chins can be incorporated later 10's or even at the 5's, however it should be at the 10's so till then do lat pull downs, pull overs or rows, they will strengthen your back till then.
Dips - try to do at least 10 and then with body weight, then slowly start adding weight on, you will eventually get the strength and the hang of it.
Sometimes some of these exercises are really a matter of getting the groove right, then it is cruising from there on.
When i first started doing chins at the beginning of high school i could barely do a couple reps. Coaches had us do negatives to reach the target rep number after we couldn't do any normal reps.
I still do this during post 5's. Negatives or clustering. Works great! =)