Here's free DJ lesson for EDM culture- DJing is about managing time and space with music. You're really a big jerk if you're an opening DJ and playing anything commercial and/or over 125 bpms (even 120 is pushing it). And here's a free DJ tip- you don't know how to DJ if you don't know how to open.
This is where tracks like "So Into You" from Chris Malinchak come into play- literally. This track is a heater- it warms up the room. The crowd is arriving, grabbing their drinks, scoping the scene. You want people bopping their heads, getting loose. You play too disco, the house heads will leave, too house and the techno crowd will bail. This track has everyone thinking 'I'm not too sure what this is but I like it, I'm gonna stick around for a while".
Along with the free lesson you get a free download. Must be your lucky day-