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Cock Pumper's Guide
About 10 years ago I started there, and have learned lots along the way. To me the most important, be super horney, be hard, be shaved down to the root of your cock, warm up with a hot/warm washcloth, stretch with lube for 5-10 minutes, enter the tube, keep pressure low, pump for 5 min then take a break with 3 min of stretching to start. Don't start with high pressure, low and slow, plenty of breaks, with the goal of building a base..... get a good tube, make sure it fits, there are several tube makers for only cock pumping. For a pump, I use a brass one from Harbor Freight, cost under $50, and will last years if taken care with. I started with flared tubes, and have graduated to a thick wall and pump with real warm water. Good luck, there are lots here who can help you on your journey.