By doing a heavy lift first, you excite the nervous system and neuromuscular junctions and turn on more muscle fibers: the "potentiation effect." If you immediately switch to hypertrophy work using the same movement pattern, you'll keep more fibers active and stimulate more growth.
Use two different loads for each set. Load the bar with 75% of your maximum. Then, slap on a pair of collars. You'll then add an additional 10-15% weight on the other sides of the collars. (The bar is now loaded with 85-90% of your max.) This will make it easier to quickly remove the additional weight before doing the drop set.
- Do 1 rep with the heavy weight (85-90%).
- Quickly unload the added weight. Ideally a partner does it.
- Take the lighter weight and perform as many good, non-cheating reps as you can. It should fall between 7 and 10. If you can get more than 10, increase the weight a little.
This method will build a lot of muscle. It'll also get you used to handling bigger weights which will translate into maximum strength gains. Although this method can be used with any exercise, it's better suited to bigger lifts like squat, bench press, overhead press, row, etc.