Anal sex and mild bdsm?

Im still relatively new to sex, only lost my virginity about 3 months ago, so im still lacking a bit of confidence. My boyfriend and I know we’re both into anal (he doesnt mind being on the bottom, not that we have a strap-on yet) and we also both know we’re into bdsm to a degree. The issue is is that i think we’re both lacking a bit of experience there, and I honestly dont know where to start. Any tips would be appreciated for how to pleasure my boy!