Drop your favorite essential oil over the diffuser. When the scent does wear off, add a few drops of essential / fragrance oil, and let them few minutes until all the oil has absorbed into the diffuser.Also you can use your favorite perfume or leftover perfume. 
 
One handcrafted cement floral oil diffuser.
Essential Oils are not included
 
Materials:
Black gravel, Cement, ECO Water proofing sealer comes with cork bottoms.
 
Dimensions:
7 cm(D) x 2 cm(H)