The biceps are muscles that are very small in comparison to other groups, however, they recover very quickly. Using a finisher strategy will ensure you've fatigued every remaining fiber resulting in great gains, not to mention an incredible post-workout pump. Warning: Don't do these sets at the end of every workout. Over a 3-4 week period, perform them 1/2 - 2/3 of the days you're training. Then focus on another muscle group. Listen to your body, if you're not recovering, perform them less.
Finisher Option One: Partnered Alternating Dumbbell Curls
Using a partner, complete the following rep scheme, alternating with each set. Each partner completes every set and rests while the other guy is working. Set 1: 20 reps Set 2: 18 reps Set 3: 16 reps Set 4: 14 reps Set 5: 12 reps Set 6: 10 reps * If you don't have a partner, complete your set, then count to whatever the rep count is you just completed, and continue to the next set.
Finisher Option Two: Single Arm Dumbbell Curl - Drop Set
5 sets of 5 reps. No rest between sets. Drop the weight by 5 lbs. for each set. Tip: If you're starting with a 40-lb. dumbbell curl, go 40, 35, 30, 25, 20 pounds with one arm, rest for 90 seconds, then do the other arm.