Adrian Tchaikovsky, author of the Echoes of the Fall trilogy from Tor UK.
The caveat is that these are my tips; any other writer may endorse none of them. Five tips, then. Not necessarily top tips, but somewhere around the upper half of the tree I hope.
To Thine Own Self Be True
The lesson is, it’s less useful to start off with the intention to write a book to tap that wildly lucrative epic fantasy market (ha ha) than it is to write the book you want. Take the story that’s trying to get out of you, put it on a leash and see where it leads. If that story turns out to be an epic fantasy story then you may turn out to be an epic fantasy writer, but there’s no sense shoving some dragons into Lady Chatterley’s Lover. Unless that’s the story you need to tell, in which case that sounds interesting, go for it.
Begin by descending
Epic fantasy is the grand historical sweep of drama taking place in an imagined world. If that imagined world is just the usual clichés hastily assembled into something like a Hollywood take on medieval Europe or Feudal Japan, there’s little solid footing there to tell a compelling story. Solid foundations are the meat and drink of epic fantasy. Not that the world should then eclipse plot and character, but good characters need places to come from, attitudes to inherit, prejudices to give in to or overcome; all of these come from the world that produced them.
The Light Fantastic
Following on, know why you’re bringing your bucket to this particular well. Epic fantasy has strengths, chief amongst them the fact that it gives a writer license to be fantastical. This doesn’t necessarily mean dragons, with or without Lady Chatterley, but make use of the genre’s strengths, flex your imagination.
Knowledge is Power
Researching the history is a good move if your setting has history backing it. Even if you haven’t settled on your setting, or if you’re trying to sever all ties to real world history, the best way to achieve (2) and ground (3) above is to furnish yourself with a solid mental toolkit. Religion, politics, economics, agriculture, couture, law, customs, superstitions… The past is a cornucopia.
Because epic fantasy has been known to become a bit invested in the armies and the maps and the who-killed-who-with-which-named-sword of the thing, remember good characters make good stories – even the bit part players. For me, solid worlds are a factory of interesting folks, churned out quite naturally by the interacting gear-train of cultures, traditions, places and past histories – things the readers don’t need to explicitly hear about, but which inform everything in the book. And because it’s fantasy, characters can be very diverse and interesting indeed.