I always held to this guideline starting out:
Basically, for your current playing song, you would be thinking about 25 potential songs (5 for the next song, then 5 for each of those for the follow-up, as thinking two songs ahead helps keep the mood instead of being completely reactionary which would lead to a skitzophrenic set), which seems like a lot at first, but there will be a lot of overlap, and a bunch of the songs will be weeded out immediately. For example, if you’re playing a song with a really strong buildup (but not a room-smashing peak), and the audience is reacting positively with some more energy (more people out on the floor or heading there, more movement and cheering, no line at the bar), then you’ll want to cull down your potential song list to just those that would maintain and even add to that energy, like another buildup or maybe even a peak. Or, if it seems like the current song is losing folks, the situation might call for a slower, downtempo song to kind of soft-reset the mix and give you a fresh chance to build up again.
Approaching it like this when I started out, I began to casually categorize all the tunes into potential categories, and wound up (at least in the beginning) with five basic song archetypes:
-The slow but noticeable buildup (starts simply, builds up in complexity over the course of the song, can be sped up to lead into an even higher energy song, few if any breaks and no real peaks but with a definite energy to the overall feel of the song)
-The quick buildup / peak (builds up quickly, usually has a break in the middle, builds up again to a peak, another break, bigger peak, finishes with a moderate amount of gusto)
-The neutral bridge (no tempo or energy change, good for maintaining energy, can be manipulated via tempo changes to add or subtract energy, to taste)
-The breakdown (may start fast or slow, quickly dissolves into a softer, more deliberate beat, very low-impact)
-The showstopper (somewhere within the song is a big break with a very simple beat, just the melody, or even total silence, all without a follow-up peak, great for dropping the energy quickly but also just as good at leading into a high-energy song with a peak for maximum effect)
This list is ENTIRELY subjective, and in no way encompasses all of the different complexities in music, not even within club music. But, sorting it out this way helped me establish a baseline “go-to” mindset when mixing. I’d be playing a song while considering, “should I follow it up with a buildup and then a peak, or should I do a breakdown first?” And for every song, I had one of each category in mind, just in case, and could react to whatever the situation called for, and then know exactly what to follow it up with. It created very dynamic, fluid mixes that were always in-tune with the audience.
It’s just a baseline, though; as you get more experience, you’ll learn how to take a breakdown and turn it into a peak, or make that super-fast high-energy song a downtempo showstarter. Other factors include key changes (LEARN TO MIX HARMONICALLY, it’s yet another factor in handling energy as, for example, moving up in key creates tension), effects, EQ manipulation, sampling, you name it. But at the core, it’s going to come down to song selection, so at the very least be thinking like a chessmaster and having in mind your 5 next moves, and then 5 follow-up moves for every one of those.
Read it again, maybe the logic will hit you the fourth time around.