he actually says he can't be bothered to go down on me!!!!!!
Are you serious. Kick this useless twat to the kerb and form a mutually beneficial arrangement with your vibrator.
Can't be bothered. Dear god.
Anyway my tips for faking it:
If you can sense he's getting near, start talking all porny and like you're about to orgasm. "Oh my god yes, that cock feels so good in me, fuck that pussy, oh god yeah I'm gonna cum, oooooh I'm cumming, oooooooohhhhh!" If he still doesn't finish after that, try "Come on and give me that big hot load of cum, I want it in my pussy/mouth, give it to me baby, I need it now."
Lots of guys feel they "shouldn't" orgasm until you've got yours, but have no idea how to get you there. If it's casual/transactional then just make it easy for them.
Tips for orgasming during penetration:
Make sure you (not him!) have access to use a vibrator on your clit. Do not for the love of god let him try to rub your clit during penetration. All kinds of awkward and clumsy.
Cowgirl:
Great for starting off/warming up with a guy who has a larger than average penis. You can control depth and speed.
Reverse cowgirl:
If he doesn't have a longer than average penis, forget it. If he has a longer than average penis then I still forget it as it's one of the most awkward, counter intuitive, non rhythmical positions I've ever attempted.