Supersets and giant sets work well for inducing metabolic stress, especially those that stress the muscle at different lengths.
Here's a skull crusher variation where I lower the bar to my nose for 10 reps, then to my forehead for 10 reps, then behind the head for 10 reps. Try it!
When do you do low reps and heavy weight? What about higher reps and light weight? Read this and finally feel good about writing your own training programs.