PLEASE HELP!!! introducing the bottle to a breastfed baby

Nanc
Hello, I will be starting work in a couple months and I wanted to introduce the bottle. Right now my son is 3 months old.
Any tips? I've been getting a lot of resistance from him. 
1. How many times should I try in one day? 
2. How long should I try with one bottle/nipple before I decide we need to move on to the next bottle/nipple?
3. Would the right nipple cause him to suck immediately? 
He does not take a pacifier so I think he's just very confused about what to do when I try to give him the bottle. He chews on the nipple or turns away.