Well, PnP is not relly a given around here because we have mappers who have used all sorts of media to create maps like paint and canvas, pen and paper and the current fav...computer using all sorts of progs. While most of the info in this link refers to the latter, there are things common with any mapping. One of the best pieces of advise is to just do something and post a WIP (Work In Progress) to receive help and guidance as you go.

Now, to your actual question and more to the pen and paper side of things. I would just start with a blank piece of paper and let your pencil/pen go for a drunken amble all over the sheet. Pick a point somewhere nearish the middle and then go like a drunken sailor on shore leave hitting all the bars he sees until he returns to his ship. Once that is done, you now have a land mass. His ship might hit another port if you think the map could use it, but you can just use the one amble if you like. At this point, you might want to look at an atlas or even google maps/earth to get an idea of what a natural coast might look like at the rough scale that you are thinking about. Either add or subtract to the randomness as you feel fits what you want, and there you have your start. The rest is placing your terrain features and signs of civilization. Again refer to those maps you checked out earlier as to what would fit according to the scale of everything.

Once you have that, take a browse through the WIPs and Tutorials to see suggestions on how things could be represented on maps of various styles and stuff like that. You never know what might suit what you have in mind and you may find new ways of looking at something that wouldn't have occurred to you before. And don't forget to start a WIP of your own because that is where you REALLY get the best out of the Guild.

Hope you have fun drawing what is in your minds eye, and can't wait to see what what you see.