Ensure surface to be applied to is thoroughly clean and free from grease. Never use polish to clean the rim (or a decal), I use an Isopropyl Alcohol spray which is perfect for the job, but I appreciate not all customers will have access to this, so a very weak mixture of washing up liquid and clean water is next best. Use a dry cloth or paper towel (not a cloth that has been used for cleaning other items). Once clean, allow to fully dry, do not touch the area as even fingerprints contain grease. Having applied the decal, it is recommended that you hold it down for as long as possible to ensure that the adhesive can ‘bite’ into the metal, please remember that all rims were produced to repel rain, mud, salt (UK) and anything else that nature can throw at them, this is probably why most decals lifted very quickly!
Again, never use polish or powerful cleaning products, this may destroy the print, this includes items such as acetone which is a solvent and will attack the print. Best to use a mixture of soapy water with either a sponge or a soft brush. If you follow these basic instructions, your decasl will last for years, mine have!