Take note that there is leather cleaner and conditioner. Personally, I just clean my wheel with an interior cleaner spray and microfiber. I spritz once on the towel, and grab the wheel with my hand and give it a solid rub down. Take notes of the cloth as you go to see how much dirt you're pulling off.
Soap and water should work fine. You can use a soft brush (boars head is what I would use) meant for leather and scrub the wheel w/ soap and water or a special leather cleaner, or interior cleaner.
I never use any armorall products or anything that has petroleum in it. That leaves it greasy looking and slick. It's the steering wheel, it shouldn't be slippery--that is dangerous.