Vacuum enlargement or penis pumping is the practice of sticking you manhood into a device. Applying air pressure to create a suction which then draws blood flow and body fluids into your private area. Forcing the spongey chambers and blood vessels in you cock to forcibly expand. Resulting in pleasurable feelings and large temporary and sometimes permanent size increases. I am going to describe one of my typical sessions.
I keep all of my acrylic vacuum tubes together in a central location. I use a step progression beginning with my 2 in diameter tube and working my way up and up. I drink plenty of fluids daily. I always try to pee first before I begin. I gently apply some form of lubricant on the head of my penis and the top of my shaft mid down. I stand up. Insert myself into the first tube. Once in and comfortable I hold the tube against my pubic bone and begin. Using a brass handled bilge pump I slowly draw the air out of the tube. It can be anything that draws the air out. You want a good tight seal starting off with a low air pressure. You will feel a surge as your penis reacts and moves in length towards the end of the tube. The skin at the base of your cock will expand and flare out. Your skin will cling to the plastic as you start to grow. The crown of your cock head will get bigger and turn reddish or purple because that is where the blood flow is racing towards. You will feel a stretch as you lurch towards the end of the tube.