What works in the supermarket can also help you to sell your writing, whether that's a novel, a screeplay, or a non-fiction book.
I'm talking about the samples tray--you try a little of that cheese or that sausage or cookie, you like it, and before you know it in your shopping basked you've got three packs that you never would have bought otherwise. In terms of writing, here are some of the ways you can let people sample your work.
If you're a novelist:
* short stories published as an ebook
* short stories or sample chapters published on a sharing site like Wattpad
* sample chapters of your novel on your web site
If you're a non-fiction book author:
* articles on related topics published in newspapers or magazines
* a relevant blog you establish, and guest posts on other blogs
* samples on your web site
If you're a screenwriter:
* short films for which you write the script, produced by you
* short films produced from your script by others (check local film schools--they often have directing/producing students looking for scripts to work with)
* a graphic novel (or chapter of one) based on your script (graphic design and illustrations students who aren't writers may do this cheaply or for their portfolio-naturally you should make a deal to pay them if and when you make any money from this)
* spec scripts in the genre in which you're strongest
Most people are reluctant to take a chance on someone new but if your samples demonstrate your skills you'll find it much easier to win them over.
(For lots of tips on marketing your work, see "Your Writing Coach," published by Nicholas Brealey and available from Amazon or your other favorite book seller.)