I purchase tracks grid them, then when i have the time put together a new mix, completely random as well.. rarely practice just don't have the time between work, my dog and the missus!
my next mix is going to be Techno/Tech House for my show and it's going to be straight up 2 hours of mixing no prep really just select tracks and of i go, makes it all the more exciting avoiding mistakes, which invariably do occur but then i prefer to do my mixing like that.
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