Goblin Ambush/Cragmaw Hideout
Sorry for the crappy pictures. I really want to figure out how to get better at photography, but I'm just trying to show off my maps.
I usually draw my maps on grid paper, often adding little details and using reusable assets that I craft (like my trees). Or use a poster and draw my own grid.
My local hobby store sells rolls of grass mats for model train sets, and I drew a one-inch grid on it. I glued it to a poster board, easy for storage.