The Supplies

• To make a reed diffuser, you will need to secure a few supplies. Visit a perfumery or check the Internet to find scented oil, dipropylene glycol and perfumer's alcohol. Get a UV resistant bottle made of glass, cobalt or amber; and a bundle of three millimeter reeds. You can find both at craft stores. Be sure to read the label of your reeds: Only real reads will absorb fragrance and diffuse scent through the air. Be sure to purchase real reeds, and not bamboo, or resin replicas.
  Make sure that you buy the correct liquids, as well. Fragrance grade dipropylene glycol combined with scented oil makes the most effective base for reed diffusers. So be sure to buy dipropylene glycol that is advertised as fragrance grade, not industrial grade.
  Also ensure that your oils are high in quality. You can use any fragrance oil, any essential oil, or any combination of oil scents, but know that any oil that contains vanillin will turn brown when exposed to the oxygen in the air.
  
  

The Process

• Next, make your scent. Combine three parts oil to seven parts dipropylene glycol in a large container. Stir or shake the mixture, but be gentle, because you can damage the fragrance if you are too rough. When the fragrance is mixed, pour it into your UV resistant bottle. Stop when the bottle is three-quarters full. Place about 10 reeds into the bottle. Add more reeds if the neck of the bottle is wide; arrange them so that they look nice.
  Each fragrance is different. If you find that the scent you have created is not strong enough, increase the amount of fragrance oil by one part and re-mix. Realize, however, that oil is thicker than dipropylene glycol. You must be careful to maintain liquid consistency. The ratio of oil to dipropylene glycol should be less than one to one. If your mixture becomes too thick, dilute it with up to 10 percent perfumer's alcohol.
  Treat your reed diffuser with care. Do not add water to the oil mixture, and do not cork the bottle at night. If you find that you cannot smell your fragrance, but the oil is not gone, replace your reeds. Their pores may be clogged by oil.
  Although your home environment will affect the shelf-life of your reed diffuser, the scent should last for up to six months. Enjoy your diffuser, enjoy the smell, and take pride in the fact that you created your decor yourself.