Don’t let your routine become routine. In other words, continue to challenge yourself even if the motions are the same. As you continue to exercise, you get stronger (obviously), so try increasing the weight, incline, reps, etc.
Right now I’m transitioning from 15 lbs to 17.5 with some exercises and 17.5 to 20 in others. It’s not easy, but totally worth it. Try warming up with your usual weight in the first and second sets, then increase weight for the third and fourth. Reps will decrease, but confidence to evolve your workout grows stronger.
**Note: I strongly suggest changing up the actual exercizes to surprise your muscles and keep them challenged. It’s really the only way to see changes.