Practice driving on snow-covered roads that are not all that busy and do this at a time of day when traffic isn't heavy. Find an big parking lot that isn't plowed all that well and give it a try. I'm not suggesting that you just go out joy-riding; but it is important for you to figure out how to do the snow driving, just in a less-stressful environment.
*Don't put your hazards on. Everyone knows it is snowing and going slower than normal. Hazards indicate an emergency, not "slow".
*Resist the urge to slam on your brakes. If you leave enough following distance between yourself and the next car, you will have plenty of time to stop. Slamming on your brakes will do two things: cause you to slide even more and if the person behind you isn't paying attention, they'll rear end you pretty hard.
*While you should allow space between yourself and the car in front of you, 17 car lengths is not necessary. A few car lengths would be appropriate, otherwise you set yourself up for the idiot drivers cutting you off.
*Try to drive as normally as possible but at a reduced speed. Usually about 5-10 miles below the speed limit should be sufficient.
*When turning, if the car gets a little slippery, GENTLY turn your wheel and gently back off of the gas. If you're making a turn, particularly a right-hand turn and you start to fish-tail or skid and you hit your brakes, you're going to make it worse. Just gently back off the gas and let your hands guide the car using the steering wheel. Your car will right itself just fine - no slamming on the brakes because you're scared you'll skid off the road.
*Stay in the right-hand lanes unless you need to be in a left-hand lane for turning.
*If the roads are really bad but you still have to drive, try to keep your wheels within the already-established tire tracks on the streets.
*If you start to skid or slide, turn your wheel IN THE DIRECTION of your skid. Do not turn away from the skid.
*If you have to go up a hill, do not at any time apply your brakes. I'm not saying "gas it and go" but if you start sliding while going up the hill try your best to keep moving up that hill and gently, gradually give it a little more gas (don't floor it). If you hit your brakes, you will #1 start to slide backward, #2 find it almost impossible to get started again and, #3 might possibly hit the people behind you.