New here, too, but have been reading for ages. I try to fine-tune my style identity every time this topic comes up, but vacillate between frustration with not being able to nail it down and thinking maybe I don't really need to define myself after all. That said, I am trying to avoid wasteful shopping after purging my closet of so much junk over the last year, so I do try to follow a few guidelines/style concepts.
I like clothes that make me feel powerful and in control. I realize that may sound a little funny. What I mean is, that when I feel really good in something vs. feeling just ok, I feel more powerful and capable. I was a very shy, overweight child who moved around a lot and often found it hard to constantly be making new friends. I had a hard time finding "cool" clothes in my size back then and never felt great. In the last 10-15 years, that has changed and I appreciate the power that clothes can have on my attitude and mood.
Sometimes for me that can mean a tough boot, a bold accessory, killer heels, but sometimes it can be as simple as a t-shirt in a good color and fit for me with some fun flats. It's not really something I can define.
I do tend towards pieces that are fairly classic, with accessories that are bold with an occasional rocker touch. When I shop these days, I do try to ask myself if I really love it, what I'd think if I saw someone else wearing it, and it feels like "me".