Tropes
It is easy to fall into tropes used by fantasy powerhouses, such as J R. R. Tolkien and George R. R. Martin. However, these will become stale quickly, so it is especially important for fantasy writers to have good creative muscles. For example, when people think of an elf, they think of long, pointy ears, slender bodies, affinities for nature, and deadly accurate archers. However, people will eventually be bored of elves with the same set of tropes. An example of a unique stamp on elves that I like is from RuneScape, a wildly popular multiplayer online RPG. In RuneScape, elves are similar to those of Tolkien in being aloof and reclusive, but what stands out to me is that they have a great crystalline city. This characteristic sets apart elves in RuneScape from elves in other fantasy games and novels.
Names
There are a plethora of fantasy name generator sites that have been part of my bread and butter as a fantasy author. However, when it comes to naming characters, races, and other important aspects of a novel, I love turning to other languages. For example, in the fantasy series I'm writing, I have a race of elephant-like people known as the "Tembo." I derived this name from the Swahili word for "elephant," so this works best for anthropomorphic races, or animalistic humanoids like cat-people in anime and manga.
Subgenres
Subgenres are portions of a genre that emphasize on certain elements, and some even add components of other genres. The best examples I can think of are science fantasy, which is what Star Wars can fall under, and paranormal romance, which is Twilight's genre. Fantasy is the most diverse genre in terms of subgenres with sword and sorcery, urban fantasy, and historical fantasy as popular subgenres. By knowing what subgenre a fantasy author wants to work with, they can better pick their target audience and plot their work appropriately.
