Hi Anthony, welcome to the forums. Thanks for the introduction.
You ask some good questions that are not answered easily. DJ-ing at it’s very core is about “knowing what comes next”. And that is something that comes from deep knowledge of your collection (keeping it very tight, no need to fall in the “let’s collect any and all music I can get my hands on”-trap) and a very broad knowledge of what is out there (and preferably what has been out there that was successful).
Gear, technology and technical DJ skills come in distant 2nd.
As for how to make a good tape, you might want to invest in the Mixtape Pro Formula course that teaches you all you need to know to turn out good mixtapes.
As for the duration, most people don’t have time to listen to lengthy tapes. So, make a relatively short tape, showing a few tracks mixed into others that give an impression of the kind of music you think would be appropriate at this venue.
Good luck and enjoy your time here.
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