I'm an anal virgin (both ways) but hopefully this link helps
https://sg.answers.yahoo.com/questio...6125455AAyS5YX
from what i've read, start with foreplay/clit pleasuring followed by slow fingering of the ass. Then put sufficient lube both inside your ass and on your penetrator. I think KY Lube is a popular option for this? Correct me if I'm wrong. Try to relaxed and just go with the flow i guess.