You can increase your perception of the size of your "equipment" by a couple of simple grooming tips.

Hair Care, part 1:

First, keep your pubic hair short. If your penis is trying to stick out from big bush of pubic hair, it's bound to look smaller. Trim your hair down to 3/4 inch in length (2cm) or so. It gives a neat appearance and makes it easier to keep clean. This also makes it easier when doing the exercises, since it's less likely to get hair caught in your grip.

Hair Care, part 2:

The radical step is to shave your entire pubic area. Many porn actors do this but I find it just too uncomfortable. The hair down there prevents chafing when you walk and sit; take it all off and you'll really notice.

The compromise (which I employ and recommend) is to shave just the base of your penis. I found that my pubic hair grew about an inch up the shaft, and when I shaved it off, it felt like I had another inch of length immediately. I also like the smooth way it feels, especially during sexual activity.

To shave the base of the penis, use a disposable blade razor. While you're in the shower or bath, lather up the area using soap or shaving cream. With one hand, get a firm grip on the head of your penis and pull it away from your body. With the other hand, glide the razor gently down the shaft, starting at the spot on the shaft where the hair begins. Glide it toward your body, working against the direction the hair grows.

Shave down the shaft all the way to the base, where your penis meets your body. Continue around the shaft, shaving the top, sides and bottom of the penis. Be careful! A nick here would not be fun.

I do this every morning in the shower. That minimizes the "stubble" and maintains the smooth feeling.

Skin Care:

Since the skin of your penis will be stretched by all this exercise, you'll want to treat it properly as well. Consider applying a small amount of moisturizing cream to the skin of the shaft and the head. I do this every morning after showering. It keeps the skin soft and smooth and helps the skin stay pliable when you stretch it.