When mine gets particularly nasty I put a veggie leaf in my hand and bring it to her face, she'll close eyes thinking I want to hand feed which it won't anymore. Then I pick it up.
I don't do this much thought because I want to train my ig to get used to being picked up, not just tricked into "not knowing". Of course you don't sneak up to it and grab it that will scare it. I just wave at it and then slowly move my hand nearer and nearer and then pet it a few times and then pick it up. Worked like a charm. Nowadays she doesn't run anymore, just puffs up and tries to look real mean and stuff.