Position is very important. Never stand straight. Always squat down a little or sit back. Always remember: your weight is in the front if your hands are in the front, your weight is in the back if your hands are in the back. Try to balance this out. Try to sit on your heels most of the time. This will give you sufficient balance.
Always aim at skiing in a zig-zag position, in an S shape, to put it simply. Hunch down a bit and then try to stand up straight. Balance the act by not putting too much weight on the skis. You will find plenty of obstacles in the snow, but don’t try to avoid them. Instead, use them as your navigation maps. Buying a good ski tubes will help in learning this sport.
Aim for the contours and ski around them. Turning will be easier this way. Learn to recognize snow bumps that are safe and snow bumps that are quite dangerous, i.e., bumps covering rocks. This will give you an edge.
And always turn using your thighs, i.e. your thighs should rotate your pelvis in the direction you want to ski. Try to rotate your thighs and maintain equal amount of pressure on each one of your skis. Finally, remember not to rush. Take a clean, nice turn using your thighs and rotate your ski tubes slowly. Do not hop. Nice and slow does it.
You may catch up speed at some point, but do not be afraid of it. It might amuse you to know, it’s easy to control your turning when you are going a bit fast. All you need is a bit of concentration and good ski tubes.