Use an isolation exercise before a compound movement to emphasize a target muscle.
Use moderate loads because the target muscle is already fatigued.
Use the method to improve the result, not just to make the workout harder. The client must still move well, recover well, and understand the purpose.
Cable fly 12-15, then DB bench press 8-10.
Month 1: learn the format and keep effort controlled. Month 2: add a set, round, or slightly more load. Month 3: increase intensity only if form, recovery, and confidence are strong.