I/we have a couple of considerations.
We have 3 good singers, I like to let one sing lead while the others get a break for a couple of songs and just do some harmonies, then put on with just one vocalist so everybody gets a break now and then.
I also try to put several songs in a row where I don't have to switch guitars unless I go out of tune. I use at least two open tunings, drop D, acoustic and in several cases a specific guitar for a specific song. So I don't want to swap every song. It only takes 10 seconds, but I'd much rather keep one for at least 3 songs if I can. SO we work around that too.
Otherwise, ALWAYS start and end with a bang. One of the guys suggested doing a slow one for the last song, no way. Wind up the set and the night with a really good rocker, and try for one of your best. In between, I like to go for 2 or 3 rockers, easier feel fast ones, then a slow tune or acoustic. We have at least 10 all acoustic ones to throw in. Then work back up to a good energetic one or two and end the set with one that really rocks. I'm still trying to think of one for the last song of the night, REO Speedwagon's "Riding the Storm Out" is one of my all time favorites. Or Doobie'Brothers' "Rockin' Down the Highway".
But whatever you do, do a really good one for that last song and pull out all the stops. Start oft the night the same way, hit 'em hard, leave 'em breathless and beggin' for more...And reserve one for an encore...I've had to do them plenty times, even as a nightclub dance band...
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