Step 1: Obtain the Supplies
Here's the small list:
1) Can. Any that's similar to a soda can would work (needs a hole smaller than the circumference of the can in which the air will escape from).
2) Isopropyl Alcohol. You can find this at places like Walgreen's or Walmart. The higher the purity, the better.
3) Ignition source. Anything that produces fire and is long enough so that your hand is out of the way of the blast would work. In my case, I used a stick with toilet paper wrapped around the end and a lighter, because I was running low on matches.
4) Something to blast hot air at. This is not really necessary, but would make the experience more fun. You can use anything, but just to let you know, the air is hot enough to ignite paper most of the time (although paper ignition might be caused by sprayed alcohol). I do not suggest using live targets, since getting burnt by the hot air is the equivalent of getting scalded by boiling water (trust me, I've tried).
Step 2: Pour the Alcohol Into the Can
Step 3: Shake the Can
Step 4: Lay the Can on Its Side
Step 5: Add Fire
1) The ignition source actually is lit on fire.
2) Your hand is not within 3 or so inches from the hole. My index finger got burnt up the first time I tried this (not knowing that hot air will come out). I felt the pain for hours.
If you did everything correctly, very hot air will come out of the can hole, accompanied by a neat whooshing sound. The force of the hot air may spray alcohol out of the can, so watch out.
To do this again, just shake the can more (if alcohol is still inside), and put your ignition source back to the hole.