The first question you have to ask yourself is of you want to go into digital cartography or hand drawn. I have always done it the old fashioned way, so I can only give you a few pointers in that direction. In general, however, it is best to begin by asking what style of maps you want to make (what you like, what you do not, type of map [regional, cities, buildings, all of them]). Since I do it by hand, I just grab some paper and a pencil and have at it. Over time you will find your style. Above all, just play around to get your feet wet!