What can i do to get cats to like me more?

I volunteer in a shelter and have been put with the cats twice but they dont seem to like me very much. They often run from me and wont let me put them back in their cage. I am very friendly and gentle with them but i kind of awkwardly pick them up because im not sure how to hold them. Its not the cats thats the problems its me because everytime someone else walks into the room the cats run to them and allow that person to pet them. I try to pet the cats and i do everything ive seen other people do in terms of petting and scratching the cats but the cats are just not comfortable around me. What can i do to make them more comfortable with me? I really like cats and usually they like me but these just dont seem to favor me in particular.. They dont try to attack or anything they just move away from me. Sometimes they let me get close but most of the time theyll move. Thanks!