I hate to do it, but there is so much written on the subject, both here in forum posts as on the main site on how to build and maintain a collection, that I have to say use the search function and read up.
In short: you can’t keep up with ALL the newest music. Way too much out there. And be careful about the “hits”. Of course beatport top15 and such will tell you what is hot and happening, but part of being a DJ is finding new music in your particular style/genre that YOU like and think your audience might like. And when playing out, you try to ease those tracks into your set and see how the crowd reacts. I can tell you the feeling of having found a “hit” before it becomes a hit is pretty nice.
These days you have a much smaller time frame to manage that though. In the old days of vinyl and CD, the time to market for music was way longer. Now a track can go viral within a day of publication on the web.
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