Ok, here’s my progression in it’s entirety(you must be able to do at least 30 regular push-ups):
Do two-handed pushups butrelax one of the arms and let the other carry the weight. In other words if someone were to look at you, they’d think you’re doing a regular pushup. When in fact one of the arms is doing about 70-90% of the work. This is the only simple step so it’s best to learn to do 20 clean reps with the free arm almost completely relaxed.
Phase#2 Side 1arm pushup
Let’s assume you’re doing the right side first. Lay on your right side of the body so that the left shoulder is facing up. Now try to do a 1Arm pushup with your body positioned this way. This phase isn’t very difficult and should greatly motivate you since you’re technically already doing single handed pushups. Again, 20 clean reps is good.
Phase#3(what I was talking of in the previous post)
After you’re fine with the above try to turn your body more and more towards the normal stomach-facing-floor position while using the free hand and the left leg(assuming you’re doing the right hand pushup) to assist. You can use the wall, the couch, the floor…whatever you feel comfortable with. But use the free hand for balance only. A good way to prevent cheating is to either use only one finger for support and/or try and keep the free arm completely straight.
The actual 1 arm pushup, facing floor, free arm behind the back. This one shouldn’t me that difficult after completing the above.
As paradoxical as it may seem, do not try to contract the triceps or chest too much, it’ll get you nowhere. Trust me, your tris and pecs will contract almost automatically(so just keep them at usual tightness). Instead contract your midsection, legs, the working forearm and grip. Your crotch will have a tendency to drop down so contracting the abs and lower body is essential.
Do not, DO NOT go to failure. Failure is what inexperienced young men do because they think more is better. To learn 1arm pushups you have to practice them three times a week or so. Therefore you can’t afford to have your recovery rates drop so much.
Well, I’m horrible when it comes to explaining this stuff so I hope the pics will help. Good luck. And remember, it’s not at all difficult and only takes a few weeks to learn.