Skateboarding is an incredibly fun sport. Skateboarding used to be some off-beat thing only young people did. But now it's a legitimate, recognized sport complete with endorsements and business participation. Its possible to earn a good living from it, like Tony Hawk. But it's really cool because just about anyone can learn skateboarding. But - it takes years of practice if you want to be a pro skater, so that's some bad news. You can do it if you want, but you know it takes a lot of practice, dedication, and hard work. Here are a few great suggestions to help you on your way.
There's more than meets the casual eye. It's not just pushing yourself along. When you're pushing-off you'll need to have a smooth, relaxed, and fluid motion. Avoid having an overly rapid and short movement.
You want a single strong motion that you can easily get into and pull out of without losing your balance. This one motion should be enough to get your board rolling fairly rapidly. Exactly how you push-off will depend a lot on your particular stance. If you're new to skating, it's a good idea to stay on level ground, and use a board that's well-made and sturdy. You want to be able to plant your foot firmly, not try to find your footing on an uneven surface. As you improve, of course this will be less of a concern.
Turning is all about holding your balance while shifting the weight of your body.
But you won't lean completely toward the back or front directions. So you'll want to shift your weight by shifting from flat-footed to either heel/ball of your feet. And your body remains upright and there's no swaying back/forth. You just might take a fall if you lean/sway too much. It'll help to use a flat surface that is even and not crowded. Avoid sharp turns at first. Practice making wide, gentle turns so you can get good at shifting your weight. When you're ok with that, practice lifting the board front just a hair so you can do a sharp turn.
However, stopping the board is a bit more involved. In the beginning, it might be better to just drag a foot to slow down. You can also try taking small-like steps to lose speed, kind of like opposite of the push-off. Instead of a fluid motion in one direction, you want to take small steps in the opposite direction.
This isn't great for your feet but it should do the trick. With more experience, you can just lift the board and drag the tail to come to a complete stop. But... you do want to avoid tail-grinding if you're going a bit fast.
If you don't practice, though, even the basics can seem tough. No person ever became a pro fast. Be patient and learn how to control that board. You control the board, if not - the board controls you, and that's a recipe for getting hurt.