If you've never encountered a penis with a foreskin, putting a condom on one can seem a bit intimidating. While it's true the process involves a few more steps than you may be used to, they are quick and easy and, once you figure them out, you and your partner will be ready to get down to business.
First thing's first: Place a generous drop of lube (I recommend a water-based or hybrid) inside the condom to both aid in application and treat the wearer to some extra sensation. Next, gently draw back the foreskin by pulling it down toward the base of the penis, causing the glans to poke out. (NOTE: not all foreskins retract easily or comfortably. Never force it! Talk to your partner about how their foreskin works.) Now it's time to apply your condom! Unroll the condom all the way to the base of the penis, remembering to pinch the tip to release any trapped air. Once the condom is unrolled, keep it in place by holding firmly at the base while you gently push the foreskin back toward the tip of the penis - this will allow the foreskin to glide comfortably during sex. Add some lube on the outside (because that's nice for everyone!) and you're good to go!