I used to poke my chickens whenever they pecked me, but it worked with some and not with others. I find that keeping movements slow is more effective. If I stay facing my chickens they'll be less likely to attack me. Oh well, I hope you find what works for you, good luck!
I find slow movements help too. I have an Ancona rooster that pecks me every time I'm not thinking about it and make a sudden movement. I also kind of bop him on the beak and he stares at me like he can't quite figure out what I did but it stops the pecking. It's like he's dumbfounded. He's still young though (and I don't know if I'll keep him long enough to know if this works when he's mature).
I heard a remedy that I don't know if I'll need to try yet since my roo is only three weeks old. To show your roo that you are in charge you are suppose to push him all around the yard with your feet when your walking. Just keep scooting into him each time you're outside. Don't let him be with the hens when you're doing this or scoot him away from the hens. You're suppose to do this for several weeks and he will stop pecking. He will get a deer in the headlights kind of look when he sees you after several times of doing this then you'll know it's working. I don't know if this really works but the lady I heard it from said it's worked with many of her roos. This may be hard to do if your roo only stays in the coop. Good Luck!