Also, what is the definition of doing too much?
DTM is an internet slang acronym meaning doing too much or do too much, in reference to the poster's behavior.
Additionally, what does how are you doing mean? ” is a common casual greeting in American English (often elided to “how ya doing?”, or “Hi, how ya doing?”), and is a friendly and usually rhetorical question (not requiring a serious or honest answer) about a friend or acquaintance's general state of affairs.
Accordingly, what does it mean by you do you?
It means something like Do your own thing, Do what you want, Be true to yourself, Do what feels right to you. Like Quora User wrote in his answer, it can be dismissive or encouraging, depending on context and tone.
What does DTM mean in slang?
Doing Too Much