Starting with a weight you can curl 12-15 times, do 8-10 reps on steep side of preacher bench, match those reps on the angled side, then stand and rep out.
Increase metabolic stress and time under tension with this mechanical drop set. Instead of dropping the weight, you'll be using an "easier" variation of the same exercise as you fatigue. The weight on the bar stays the same.
Set up at a preacher curl bench with an EZ-curl bar. Use a weight that you could curl 12-15 times. Do 8-10 reps on the steep, vertical side of the bench. Hold each rep for a 1-second contraction at the top.
Move around to the angled side of the bench and try to match the rep count from the first part of the set, with a slight pause in the stretched, bottom position of each rep.
Now stand up and rep out as many curls as you can.
I've titled this article TNT (Tips-n-Tricks) for a very good reason. Many times it's the small things that make the biggest difference. Usually when reading a new book or article you walk away with one good idea. This one idea could've been presented in a paragraph or two. So I got to thinking, why not just provide all those great ideas in a format that cuts out the BS? What you're left with is pure TNT, the stuff great explosions are made of.