When to Use What:
Penis-in-vagina intercourse: Condom and lubricant
Anal Intercourse: Condom and lubricant (ALWAYS use a new condom if switching between vaginal and anal intercourse)
Fellatio ( "giving head" or "blow job"): Flavored condom or unlubricated condom with flavored lube (latex by itself can taste kinda yucky). Latex gloves if combined with manual sex.
Manual sex ("fingering", or "hand job"): Latex gloves, lubricant
Cunnilingus ("going down" or "eating out"): Dental dam or saran wrap barrier, lubricant.
Analingus (or "rimming"): Dental dam or saran wrap barrier