Mimicking occurs when a perpetrator or anyone else is instructed to act or dress like you. This can look like wearing an outfit that you are wearing at that time, wearing clothes that look like your clothes, or the clothes of people you know/are close to you.

It also can look like copying your mannerisms because these are personal to you, nobody else will notice, but they are designed that way to catch your attention while blending in.

I have seen people doing dance moves that I do to joke around, it can be an unnatural or out of the ordinary motion you took recently under surveillance or while you thought you were in private like reaching for something or maneuvering yourself a certain way.

Copying the way you wave, peace signs, maybe they engaged in Priming (psychological) you with a video on social media and then playing it out in public.

It can look like a lot of things but you will know it when you see it.