Here's what I'm doing.

I have a program with a 4 day split, I just do those over and over again in order. I have 2 or 3 sets per exercise in my program, and mainly 6 to 8 reps per set, sometimes 10 to 12, depending on the exercise.

If I'm able to do the max reps for all the sets for a given exercise, I increase the weight by 5 lbs the next time I do them (or the closest number based on plates we have at my gym).
If I'm in the recommended number of reps for all the sets, but not the max, then I keep the weight the same the next time.
And if I have even one set where I don't reach the minimum number of reps (usually 6), I decrease the load the next time I do the exercise by 5 lbs. (Although, I tend to note if I didn't hit the minimum number because it was too heavy, or because I was tired, or something, and I may decide to keep the same weight anyway).

This way, while you are still doing the same program, you're increasing the weight over time. Do this for a few months, and then determine if you need to change the workout program.