That said, I became a member of Fimfiction and needed an avatar. My first avatar was actually a screenshot of a blue tuba playing pony from the Gala episode. I wasn't satisfied with this and needed to make my own avatar, so I downloaded Inkscape. My first vector would be "Hairiderpy," basically traced from a Bridle Gossip screencap of Rarity. Not long after, I would update my avatar by throwing a sousaphone on it and altering her coat and mane colors again to Beauty Brass.
Since then every story that I wrote for Fimfiction would have cover art that I vectored myself. A couple of other authors even made requests, and for a while I obliged them.
My "style," if I can claim to even have one, has evolved from taking one pony screenshot and turning them into somepony else to doing pretty much the same thing with Equestria Girls. Rainbow Dash makes a great base for Derpy (now Muffins) or Raindrops when I am so inclined, and Twilight Sparkle has always been great to turn into Blossomforth.
Over the years, some things worked, and others didn't. I was never good at making someone else's OC to their specifications. Equestria Girls' hands are the devil. Bon Bon is still my least favorite pony, not that it stopped me from vectoring her at least three times, which is more times than I've ever vectored Timber Spruce.
Derpy, Beauty Brass, Blossomforth… I had to think hard about who the last pony in the window should be, and went with Fiddles because it just made sense. I mean, sure I may have done more Sunset Shimmers and Fluttershys over the years, but Fiddlesticks is one of the earliest… and I'll admit that I've shipped FiddleBrass in an ongoing unpublished story.
All of this grew out of a desire to be a better writer and artist… it might not be easy to see the progress, but I know it's there.