I started box squatting about a month ago. been doing them 5x5 1 inch lower than parrallel. started with 315, and now at 365 5x5.. [ Also been doing stiff leg deads 5x5, and seated calf raises 5x12. on this same day ]

What is the best way to do box squats? Rep and set range?? What is best to do in addition to box squats??

Thank you