Right before my set, I do a couple of things for really hard-core lifts like squats:
1. I play a motivating song on my Ipod. Typically metallic (i.e. harvest of sorrow)
2. I use imagery. Results are clear on the efficacy of this technique. I image myself performing the lift successful, and realistically just like I have done before. And I often image myself doing 1-2 extra reps than I have done before. I image myself lifting fluently, and confidently. Then I do my lift. It is important that your images are realistic and similar to the environment and tempo that you lift.
3. Before and a little after my imagery, I'll either jump up and down, or move around a bit to get my nervous system ready to go.
4. I use positive self talk before, sometimes during the lift. Ronnie does this (i.e. nothing but a peanut, light weight, etc.).
5. When I perform the lift, I focus on the process. I don't worry too much about getting a certain amount of reps, just getting the most reps that I can, and focusing on each lift one at a time. Results show a process oriented mentality during activities can improve performance, decrease anxiety, and increase self confidence. Discussed more here, http://www.abcbodybuilding.com/goalsindex.php
I think routine is vital. When I perform my lift, I notice nothing else around me. I am completely focused on the task at hand.
Another piece of advice I have is choosing realistic goals. If you choose something unrealistic, like lift 25 pounds more than you have ever done, the anxiety is so high, that it is hard to be confident or focus on your task as much. So try and pick realistic weights more so than not.
A spotter can also be gold if you have one. They can motivate you to get an extra rep or two, and do the shouting for / with you. [img]/forum/images/graemlins/grin.gif[/img]