i wouldn't worry about getting big air on your 180s just try and get used to turning you head and hips and skiing switch. 180s aren't anything thats going to look super sick (for the most part) especially if you're just starting out, you just need them to move onto other shit in the beginning. work your way up from rollers to small jumps so that you're comfortable in the air and not floppin like a fish outa water.
rules of thumb for the future tho keeping your body tight in the air and bending your knees makes you look better and in control. and real important wherever your head is looking your body will follow.