How do I choose a snowboard to buy?

Best way is to try before you buy. Lots of places let you try a board for an hour or so although you normally have to provide your own bindings. If you dont have bindings these can be hired for very little. The size and shape of your board depends on what type of riding you would like to do (eg all mountain, freestyle, racing) for a begginer all mountain is probably best, start off with a length that comes to about your chin, a little lower if your skinny, taller if your well built. Foot size also comes into play as your toes and heal should go over the edge in order to stear but if they go over too much they will get stuck in the snow. I hope that helps