Here's how to do it: Place you back foot right on the center of the tail (as if you were doing a pop shove it) and your front foot in the kickflip position. Some people find it easier to keep their front foot a little bit closer to their back foot, to get the perfect flip. Snap down on the tail with your back foot and shove the board behind you, causing the shove it. Right before the board starts to turn 180, drag your front foot up towards the nose, and off the side, causing the flip. Now the board should be turning 180 and flipping at the same time. Wait until the board has finished flipping and rotating, hover over it, land on the trucks and ride away smoothly.
After you master this trick, it's time to move onto the backside 180 kickflip, or the 360 flip.