what I do now for a workout:
All Reps 10-15 and always for 5 sets.
first 2 sets are warmup, 3rd set a challenge in the high end of the reps (15)
set 4 is a challenge at 11-12 reps ( but before absolute failure)
Set 5 go for broke but with tight form, focusing on slow decent and firm contraction
dont over extend in the bottom, dont contract too fast
basic rules:
do all Pushing muscle one day ( Chest, Delts, Tris)
do all Pulling muscles another day ( Back, Bis)
do Legs on their own day
and of course have a cardio day for endurance, for me that means a real RUN outside for 30-45 minutes.......