There's that saying:  "Dress for the job you want, not the job you have."  I've always felt like that leaves out the middle case:  If I have the job I want (and vice versa), then how should I dress?  We live in weird and modern times (or maybe it's just a function of where I've worked), but my employer has never officially specified a dress code.  They'll say things like "no open-toed shoes" or "no shorts," but that leaves a lot on the table. 

Since I worked at my last job for a while, I became sort of a subject matter expert, so my "work" preceded me in the sense that people understood what I did and what I was capable of.  My attire or physical appearance was completely irrelevant, so I mostly dressed "down" unless I was meeting with customers or whatnot. 

At my new job, I've been dressing "up" because I haven't been there long enough to have a reputation.  I feel like if my "work" doesn't yet have a voice, my outfit probably should. #business