The easy ones. No..really, this depends on what trick you are looking forward to learn. For example, you may want to learn something impressive like the Triple ThumbSpin. In that case, it makes no sense to start by learning the Sonic. However, if you don't have any trick in particular that you want to learn, any basic trick should do. Most people get frustrated with the large amount of tricks there are, and they often end up trying to learn the most difficult tricks (which are the most impressive ones) first.