To me, it's relatively hard to completely miss the boat on steampunk if you have at least a basic idea of the concept. It's Victorian science-fiction. From there, it can go in an infinite number of directions. The one thing that is important not to loose sight of is the "punk" part. Not punk as in "spiky hairs", punk as in home made (or at least artisanal). I often say on panels that the only way to completely fail is to buy something in a mass produced box that says steampunk and to wear it as is. From your posts, I don't think that's what you're going to do
Yes gears and goggles are staples of steampunk but they are not required. Like was said before, gears are cooler when they seem useful. They can be used in jewels and things like that but with moderation. Yes they were the center of the technology of the time but today, you don't see everyone wearing microchips. Again, it must make sense. For example I made a brooch out of gears but it's supposed to represent the symbol of some engineering community so it makes sense.
The one advice I give to those who are beginning in steampunk is to start with their strengths. Create a costume that requires mostly the use of skills you master. You will pick up more skills as you go and you can upgrade it. Steampunks costumes usually contain a lot of layers and accessories so it's easy to have them evolve over time. But you seem to be well versed in costume making so you shouldn't have a problem on that side.
PS: Spats are awesome.