This tip is a short and simple one. I find that if I have a long workout planned for the morning, or even a short one for that matter, it's much better for me if I set all of my stuff out before I go to bed. It's much nicer to wake up in the morning and relax before the workout than to feel like I'm rushing myself trying to get water bottles filled, tires pumped, Garmin pieces all together, whatever. It may not seem like much, but it really is.
It is even more beneficial to pack the night before when you are doing a long workout, or traveling to your workout location (pool, driving to meet up with someone, whatever). It gives you a chance to get an almost "pre race" experience. When I am preparing for a 4 hour bike ride, the night before I make sure that I have all of my water bottles and all of my nutrition, whatever spare tubes I will taking, and any other things I may be using on my ride. Then when I wake up in the morning, all I have to do is go through a quick checklist to make sure one last time that it's all there. And as an added bonus, it gives you the option to sleep in for just a few extra minutes if you'd like!
I personally do this just about every night, since I almost always have early morning workouts. It's very nice to be able to take my time waking up instead of hearing the alarm going off and waking up in panic mode because I now have to find all of my required items mentally prepare for my workout at the same time. Try it out...I'm sure you'll like it.