Your style is a part of you. You might say that your style is like mine,or Tolkien's, but it is really only your style. Maybe your particular styleis better than mine. Maybe you are so good that people bow down to youin the street. Maybe you are so good that people say that they draw mapslike you. You tell them that no one draws maps like you and to get up outof the mud, got it? Style is nothing to flaunt. Let people admire you,don't force them to. Trust me, I wouldn't like it if you came into theroom one day and told me that you were better than me. Try to copy someone'sstyle, but recognize the presence of your own creativity. A person in thestreet should be able to say "Oh! That's one of Bobby's maps!",not "Now is that Sue's, Tom's, or Bobby's map?" 

Stick to one style 

Coherence in a map is one of the prime goals of it's artist. You wantyour mountains to look like the other mountains, to a certain degree. Uniformityis to be discouraged, but make sure that your map is pleasant enough. Awell designed map will have that aesthetic appeal that draws people intoit: it should be a story in itself, not just a reference. Look at layoutfor ideas on how to keep your map looking good. But be sure to rememberthat it is the little flaws and differences in a map that make it personal.That is why fantasy editors hire a person to make maps: a computer generatedimage is only good so far. 

Teach yourself 

Teach yourself what you like to do with your maps. If you like to placemountains in a way that is contradictory to someoneelse's style, go ahead and do it. Forge ahead into previously unexploredareas of your map and change them to suit you. After all, the map is reallymeant to please you. I do not know of an artist that painted pictures thathe didn't like. If you do, then you are more enlightened than me. 

Some rules are definite. 

There are, however, some rules to mapmaking that apply everywhere. Forinstance: do not make your mountains three inches tall and 3 centimeterswide. Just use common sense. Rivers always follow the riverrules, unless a magical force or something is holding them at bay. 

The expirement: 

Now comes the test of your skill. Find a book that you have never read,and that has a good (or not so good) map. Make sure that you do not studythe map in detail: just glance at it. Now comes the hard part. Tear themap from the book carefully, making sure not to rip it in half. Be surethat the book is a cheap soft-cover, and not a first edition Fellowshipof the Ring. Normally I would be appalled at the thought of mutilatinga book in such a way, but it is necessary. Quickly now, make a rude sketchof the map, tracing it's features through your
memory. This sketch should show the placing of mountain chains, shorelines,and maybe some forests. Rivers are not required, as they are very hardto remember. Now, read the book a few times. In the mean time, practiceyour maps. Anything will do. I usually go off in a corner and jot downa new little world, and then work off of that. After reading the book forthe third time, trace your way through it and add to your map. Once youthink the map is complete, revise it and compare it to the real map. Whatwent wrong? What went right? Why? If you wish, practice this a few times.It is only really necessary once. 

(note: by the time you complete this expirement youshould have run through this entire guide. You should begood enough to produce an acceptable final draft.)