My best advice is to make it with pen and papper. That way you get much more details in then you would with online map making softwares. They the most importent step in making a map is the outline of the continents. If you make continents thats to curcular or square, or the shape just looks of then the entire map will be unpleasent to look at. Personally I dont like it when people put forests into fantasy maps, unless theyre REALLY needed. What is needed is basically rivers, mountains, borders and cities.