I'm about 6 months from graduating with a degree in game art and game design. Meaning I'm learning 3d studio max, game theory, and Level design, scaling, etc. let me just start by saying you're talking about a HUGE undertaknig. take a look, like was said earler, at the credit list of any game. you're also taking about 2-3 years for good development. bbut, yes, it's doable. I'd love to try to make some renders of character models in Max. I don't have alot of practical knowledge yet, it's all mostly theory right now, but Hey, got to start somewhere, right?
As far as game design goes, there are a few steps. Obviously, it all begins with an idea. What type of game, Etc. Onmce you've got the basic idea of what you want, sit down and write down as much as you can. Once you've got your ideas on paper, do your best to make a Traditional Board game out of your idea, replicating the games rules as best you can in this medium. the purpose of this is to test the playability of the game. If you can't make this work, keep tweaking your game idea untill you can make it work. a game is a game is a game, regardless of the medium of which it is played in.
the next step is to design the story, and the characters. Color choice is extremely important. the main character needs to be wearing colors and details that differ from everyone else in the game, to prevent the player from getting confused. A simple example would be, if hour hero wears a red shirt with yello pants, and a big metal shoulder pad, then no one else should dress in that combination. This holds true for all Player characters.
Draw a sketch of the main character in a T pose. That is, standing, legs slightly apart, arms raisd at their sides in a T position, You need a minimum, of front, Side, back, and Top. you also need views of this yto be in-scale with each other, AND you need all his accessories as well. the more detail you can poor into this design the better. face, hair, ETC. as this is the drawing from which your artists will vreate the character. sometimes it's best to draw the character naked, and do the clothing separate.
There is ALOt more to it, but that gives you a place to start.
