Calories - Eat, Eat, Eat
Creatine - 5g pre workout
Beta Alanine - 3-6g daily throughout day
Glutamine - 5-15g post workout
Norwegian Fish oil or Flax Oil 3x daily
TONS of Water
Cut back on cardio
Focus on mass builders (squats, presses, rows, pullups, lunges, leg press)
1-5 sets of 8-12 reps to fatigue for hypertrophy (muscle growth)
Rest period between sets - 30 to 90 seconds to promote testosterone production
Don't exceed 4 workouts a week. Keep workouts under an hour.
For what it's worth, I am a personal trainer.