1. Cup and stroke them.
No, this isn't some weird golf metaphor, although I'd be surprised if Tiger Woods hasn't used those very words in the bedroom before.
If there’s anything Hollywood has taught us about testicles, it's that they're sensitive. And like any sensitive body part, light stimulation across the skin can be pleasurable. It helps that they're in the vicinity of the main attraction at his sex theme park, too. Cup them in your hands, and lightly jostle or stroke lightly with your fingers. For the love of god, just don't squeeze.
2. Lick them.
Preferably, this would be a precursor to oral sex and, in general, part of foreplay. It's not something you'd stop mid-coitus to do. (The same goes for any of these, really.)
How you want to approach it is up to you — anything will feel great. Just treat it like a tease and build-up the suspense. It's almost the male equivalent of kissing your inner thigh and around your vagina before he goes down on you. It's the opening act.
3. Play with them during a blowjob.
There's almost nothing you can do during a blowjob — other than bite or vomit — that doesn't enhance the experience.
The only thing better than one sex act is two sex acts... at the same time. You probably have something you like while having sex — having your nipples played with or your hair pulled — that heightens the stimulation. Just remember, be very careful with them.
4. Kiss them.
Though this may sound like one of the weird ways to play with his testicles, it isn't. Maybe you can't quite commit to having them in your mouth for whatever reason, but it feels fantastic to have sensitive areas kissed.
The best analogy I can come up with is the neck. Kissing his testicles is like making out with his penis's neck. LOL.
5. Suck on them.
This really goes into the same category as licking them in terms of an explanation. You probably want to do both leading up to oral. My word of advice is to be slow and gentle. Testicle pain hurts so much, it can cause physical nausea. And getting too aggressive could cause a mishap that cancels the whole encounter.
When it comes to this package, just remember: you take care of it, and it'll take care of you.