USP is an abbreviation of "Unique selling point", and it is one thing that makes you stand out from the rest of the artists out there.

Your USP can be the way you sound, the way you look, a certain way of manner, you can create a new mashup of genres, your lyric themes, etc. You just need to stand out in some way, and in a good way. You can of course always just create great music and don't bother these kind of things, but most experts and musicians would probably say that it's a lot easier if you have an appealing and unique appearence.

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