Purchase DMSO. DMSO is a solvent that is made as a byproduct in paper mills.

Set up a distillation apparatus. The essence of a distillation apparatus is that it contains twoo separate glass containers that are connected. One of the containers is used to heat the material to be distilled and the other is used as a cooling/collecting chamber.

Fill the distilling chamber with DMSO. This will be the portion of the apparatus that will be heated.

Depending on the purity of your DMSO, and your desired purity of MSM, you may need to boil off impurities first. To do this, you will need to heat the DMSO to below its boiling point, around 170 degrees Celsius or so. Place the distilling chamber in a liquid with an even higher boiling point (glycerol works well) and then heat that liquid to 170 degrees (you can measure this with a scientific thermometer). After the distillation chamber has been sitting at 170 degrees for 15 minutes, pour out whatever has accumulated in the cooling chamber.

Boil the DMSO. Raise the temperature to above 189 degrees Celsius and it will boil. As the DMSO boils, it will react with the air to turn into MSM.

Collect the MSM crystal from the cooling chamber.