Don’t concentrate so much on the exercises. I only grab while stretching and never bother to pay attention anymore. When your cock slips out of your hand, you’ll notice. Same goes for jelqing, don’t concentrate so much on it, just do it unconsciously. In the time you can do all kinds of things while growing a bigger dick :) .
To combat the itching in the hand, switch hands. When one begins to edge, use the other. I’ll also advice you to train the muscles in your hands. Buy a billiards ball and squeeze in it. Hold as long as you can and repeat 10 times. This will terminate the itching in a short time.
Finally you should ask yourself if you really want a bigger dick or not. If you really want to, you should accept that you need to put effort into it. We all would like to wake up tomorrow with the ideal dick, unfortunately life don’t work that way.