Prepare a mixture of 2/3 ammonium nitrate and 1/3 clean sand. The sand should be preferrably 50 mesh. Add the mixture to a flask or other heat-resistant container with a top that can be adapted to a tube. Another container is filled half-way with water, and the tube is submerged. The second container should also have a lid that is adapted to a tube. This second tube should be attached to receiving bags, which will be where the laughing gas will be collected.
Heat the glass container to 210 degrees Celcius, maintaining that temperature. Anything higher than 230 degrees will certainly cause an explosion. A brownish/yellow gas should be emitted from the ammonium nitrate. If the gas that rises from the second container is not clear, turn down the heat a bit. Once the bag is full, continue to replace each bag until there is no more gas.