If you are just going to the gym without an idea of what you are going to do or even just a general idea, you are doing it wrong. To make the most of your workouts, you need to have workout routine completely pre-planned before you start.
I have been working out for 24 years, and my absolute best workouts have always come when I have my workouts planned out, with all the exercises I am going to do. This eliminates wondering what you are going to do next while you are performing your current exercise, and lets you concentrate better on what you are doing. In addition, you can prepare visually and mentally with what you will be doing the night before.
I have not been doing this for quite awhile. I would just head into the gym and do my typical routine but try to change it up a little bit. Today, I started posting the Workout of the Day and used my own routine, printed it out and had it all ready to follow this morning. Let me tell you, my workout was phenomenal. One of the best chest workouts I have had in a long, long time. Great concentration, strength and pump. Just followed my own printed routine and knew exactly what I would be doing. No thoughts or messing around in-between sets wondering what I would be doing next, just a great workout.
I will be posting my workouts the day before on the Workout Calendar. Feel free to click on the workout, and print it out so you have a map to fitness to follow. These workouts are built for myself, so you may want to modify them to your liking. They will change often, to keep your body guessing. Give it a try and let me know in the comments what you think!