1. Before you put a lot of time into 180 ollies, make sure you feel comftorable with regular ollies.
2. Unlike the regular ollie, a frontside 180 must be practiced while rolling, as it is speed that aids in the process of turning 180 degrees while flying through the air. So, push a couple of times.
3. Once rolling, bend those knees and pop and ollie.
4. As you begin to travel up, and your foot slides toward the nose, start to turn your body. There's no way to exactly describe how to get your momentum shifted so you're turning without using levels of math that would give Albert Einstein a migraine, so we'll just leave it for you to experiment with.
5. The important part of the 180 aspect of the 180 ollie is the speed of your 180-degree rotation. A frontside 180 (backside, too, for that matter) must begin its rotation immedietely upon smacking the tail, and it must end just as the wheels are landing. And there's one thing you need to keep in mind: the longer you're in the air, the slower you must turn.
6. Reread 5, so you understand it.
7. Land with your knees bent, and convince yourself that you're now going backward. If your mind gets confused and freaks out, you're not going to bleed. Not that bleeding is necessarily a bad thing, but it's good if you do it less than once per day.