Naturally the best way to support the author is to buy his books! Head over to the kindle store (link) or go to the shop tab (link) to buy digital and physical editions respectively.
If you want to tip me a few pounds then the place to do that is over on Ko-fi. And thank you!
For those of you who wish to help out a little more I have set up a patreon (link). This provides a guaranteed income for me each month and helps spread out my income throughout the year. If you've bought everything of mine that interests you but still want to help production of future books, Patreon is the way to do it.