Welcome to the board! I would suggest what I did. I was getting hungup on the content for my first map being really good, from the start, but all things take incremental changes in life and so does art... I would just grab some sketchbook a number 2HB and !sketch!, in a conceptual analytical and freeflowing way... don't worry about what it looks like, focus on the overall structure of the world... mass out mountains, forests, plains, seas, bays and oceans and of course rivers... then redraw it, with more detail and maybe at a larger scale then the orginal. Anyways... take this advice, get it out of your head and on paper, otherwise you will forget ideas that could have been captured on plain paper... you will thank yourself later.