Learning to deep throat

I have tried to deep throat my boyfriend several times and couldn’t do it without gagging. We were on a double date with some friends of his and we went to their house for some drinks and smokes. We were pretty high when Judy pulled her boyfriends pants down and began sucking him, she took him all the way into her mouth. His cock was longer than my boyfriends. I watched in awe as she sucked him in and out of her mouth. I was rubbing my boyfriends cock watching. She saw me watching and asked me if I could do what she was doing, I said no. She told me to come and kneel beside her and she would teach me. She had me sucking her boyfriends cock telling me breath through my nose while swallowing his cock going up and down at the same time. I was able after a while to get all of his cock into my mouth. She was sucking my boyfriend while I practiced on hers. They both cummed at the same time. We had a wonderful time sucking and being fucked. Me and Judy became best friends sharing many cocks.