The wet method guarantees an application free from bubbles and imperfections.
Pour a half-spoon of washing-up liquid in the spray bottle(not hand soap), then fill it with water. Mix well and then spray evenly across the waterproof surface (glass, metal sheet, plastic, etc.) where you’d like to apply the decoration. For best results, wet also the face of the sticker that must be applied on the surface to be displayed.
Except for the removable stickers, in order to have an application free from bubbles and imperfections the “dry method” is advised for applying stickers and decals only in case of small format decorations, or on surfaces which are not waterproof.