Help with parakeet???

I have a 4 month old parakeet. He is pretty nice for being so young. He does bite and I wanta know how to make him stay on my ifnger and not bite me when I try to get him on my ifnger. His wings are clipped but he still runs away. I dont like it when he bited me so how can i get him to understand that my finger is ok. I WANT HIM TO TRUST ME . He will stand on my finger but when I try to get him off his playset onto my finger he bites me. I slowly put my finger under his belly and he quickly bites me.