In an ongoing effort to help out any faithful readers, I will start posting helpful workout tidbits that I have gleaned over the past decade. I can't be a cynical pessimist all the time.
1.) Do exercises that require lots of technique first in the workout. Doing exercises that require lots of physical and mental energy late in the workout increases the risk of injury.
2.) Choose multi-joint multi-muscle exercises over single-joint single-muscle exercises. I.e. stay away from dumbbell bicep curls and do Chin Ups instead.
3.) Take off your clothes and stand in front of the mirror; with the exception of your abdominals, choose exercises that train all the muscles you can't see more than the muscles you can see.
4.) Endeavor to make the majority of your training ground based. The overwhelming majority of the exercises you choose should require that you stand on your feet and balance both yourself and the implement you're lifting. Fire immediately any personal trainer that has you sit down on a machine to work out.