Generally, I tell everyone to do a 5/3 / 1 program as it is, regardless of the age or training. Of course, if you are a trainer and you are using a program with a beginner or a newly trained athlete, just use your knowledge to make any needed changes – though they should not be too much. Now if you are just starting out and working without guidance, it is probably best to stick to a basic plan.
One of the worst things a young mentor can do is take advice from other beginners on the message boards, they usually have all the advice and no experience. Below is one of the first modifications for beginners, and it works. 531 is a subtle, simple way to add extra work to the big lifts without compromising the system or philosophies it is built on.
The system is set up the same way, it takes up 90% of your size and works slowly. All percentages are based on that size of training. Each day does ONE task for each category listed below. Do a complete 50-100 repetition for each task. If you are too weak to find all the repetitions just select TWO steps to complete the complete repetition.
This is incredibly easy to do. The three options are: push, pull, and one leg/spine. If you do not understand some, many, or some of these it is probably because you have not read the book and do not have a basis for understanding diversity.
Push: dips, push-ups, DB bench / incline / press, triceps / pushdown extensions
Pull: chin-ups/pull-ups, twisted lines, lines (DB / machine / BB), face pull, belt splitting, lat pull, folding
One Leg / Spine: any abdominal activity, back lifting, the retreat of hyperextensions, lungs, step-ups, Bulgarian single-leg squats, KB snatches, swings