Now that you've got it all set up and the corn (or whatever) is fermented and hooked up to the beaker, turn the valve on a bit to drip some smelly stuff of your holding tank into your beaker. Turn on the sterno or bunsen burner to a high flame so it will heat up the beaker. Turn on the cold-water valve so you have cold water flowing around the condenser at a trickle. If the water coming out of the condenser is cold, turn the valve so even less water is coming out, because you don't want to use too much water. But, if it's warm, it's not doing its job. Keep the water coming out about lukewarm.
As this thing's just starting up, keep a good eye on your thermometer. You want to keep the temperature just above the boiling point of alcohol (which is less than the boiling point of water: 212 degrees) but below the boiling point of water. This is so you can separate the water from the alcohol by turning only the alcohol into steam, and you can get better stuff. Now, watch it, and adjust the valves so the fermented stuff coming out of the holding tank just equals the steam going up the pipe, and it won't fill up or boil dry. Adjust the cold water valve so the water coming out of the surgical tubing is slightly warm. Now, wait. Read a book, but always keep an eye on the still. When the holding tank is empty and the beaker is dry, you are done. Don't expect this to go very quick, however.
If you like almost pure alcohol, distill it again. If you do it right, you could have no water at all inside your liquid high. However, even I haven't been able to get a batch that good. All it takes is practice and getting to know your still. They all have different personalities.
Offered by Steve.