Cosmo tells me not to "bark orders like a drill sergeant," ("DROP AND GIVE ME FIFTY THRUSTS! HOOAHH!"), but I think one of the hottest kinds of sex is the kind where one partner knows exactly what they want, to the half-inch and half-second, and is able to tell the other person in real-time.
I'm not talking about "I want you to put your finger in my ass," here. I'm talking about "I want you to put your finger just a little in my ass and let me relax... okay, now a little further, okay, add a little more lube and then push it in... oh yes that's good, bend it forward and rub my prostate but don't thrust and let me get used to it again..."
It's an interesting power dynamic, it's excellent communication, it's just plain fun on both sides, and there's something wonderful about just how in touch with your body you can become by doing it.
The hard part, even in a very supportive relationship, is giving yourself permission to do it. My default "script"--somewhat culturally learned, somewhat my own tendencies--is to basically play "hot and cold" with my sexual responses. I'll stop you if you do something unpleasant and I'll encourage you if you do something nice, but when it comes to what these nice things are, I tend to just take what I'm given. I worry that I'll ask for something my partner doesn't want to do, or that I don't even know what I want.
The truth is that my partner, if they're any good at all, wants to do most things that make me happy and is perfectly capable of giving an non-horrified "nah, not that" if they don't. And more deeply, the truth is that my body often does know what it wants, when I listen. My body is amazingly adept at knowing just exactly how its own pleasure works, when just a touch more stroking would be perfect or whether I need you to hold just right there don't you dare move, when pain will hurt and when pain will feel better than coming. The truth is that I have no problem at all knowing that the best things in the world are deep firm pressure in my pussy and big bruising bites on my shoulders. I just have trouble believing and saying it.
Cueing your partner through sex isn't something to do every time; it's too one-sided and frankly could get annoying if you always did it. But it's a wonderful exercise in saying--and in knowing--exactly what you want.