Try doing pyramid sets. Start out by doing 4 solid dead hang pull-ups. No kipping! Take a break. Next set, do 5 solid dead hang pull-ups. Take a break. Repeat and add 1 rep to each additional set. Stop when you can't complete the next +1 set.
- Don't do pull-ups everyday. You can do them every other day. On your off days, just try hanging on the pull-up bar as long as you can for 3 sets. Part of the actual pull-up exercise is being able to support your own body weight. Hanging on the bar will help develop your grip strength and will make pull-ups a little easier.
- If you arch your back a little, it helps distribute more of the workload to your lats. If you do pull-ups with a straight body/back, then most of the workload goes to your arms.
- If you can get a spotter, try doing forced reps. Do as many pull-ups as you can in one set, and then ask the spotter to assist you, and do 2 or 3 more reps in the same set.
DO NOT have the spotter hold your legs/feet. That's the incorrect way to spot someone on pull-ups. Ask them to place their hands on your back and give you a gentle supporting push, upwards.