I'll try to make it clear.
RAMPING refers first and foremost to a progressive activation (ramping up) of the nervous system to help you lift more weight. The actual application of this is also a form of ramping in that you are gradually increasing the weight from set to set.
BUT keep in mind that the important thing is to optimize the working state of the nervous system, not the actual act of gradually adding weight. The MORE A SET IS DEPENDENT ON THE WORKING STATE OF THE NERVOUS SYSTEM, THE MORE EFFECTIVE RAMPING IS.
The nervous system is most important with loads/rep styles where force output is maximal. This means that it works best either with heavy weights or explosive movements.
Sets of 6-10 reps are too "light" (in relation to your maximal strength) to be heavily reliant on the nervous system. And as such this rep range doesn't really require or responds well to ramping.
Because the goal of ramp is to gradually increase your performance capacity from set to set. In essence, your last set should be the set where you are able to perform at your best.
To get better and better from set to set requires the interplay of two variables: activation and fatigue; both are created with every set.
Every set you do creates some fatigue and causes some activation.
The goal is to create as much activation as possible with as little fatigue as possible.
Higher reps cause more fatigue (more work) and activate the nervous system less (less force output). So the end result is that it is hard to get a significant increase in performance potential when using higher reps.
So I recommend NOT ramping when doing higher reps. Perform 1 or 2 lighter sets (e.g. at 75 and 90% of the weight you want to use for our sets) then jump right into it. Obviously if you are doing a big movement in which you can handle a lot of weight (e.g. if you plan on using 600lbs for 10 reps on the squat) then you might add a few more lighter sets to get the body prepared, but this is not really ramping.