Especially with glass panes, it is important that the substrate has been thoroughly cleaned of dirt and dust. In this way, unattractive inclusions under the film can be prevented after it has been glued on.
Adhesive lettering and motifs without background are delivered on a transfer foil. You can stick these on as a whole and peel them off after assembly. The individual components then remain on the window pane and stick to the right place. (You don't have to stick on single letters).
Flat adhesive foils (rectangular, round, etc.) you get on a protective carrier paper, which you can simply peel off. Then you can stick the sticker to the desired place and press it on. As a help you can use a squeegee, a credit card or similar carefully (scratch...).
Wet bonding is recommended, especially for large surfaces: The pane may be sprayed with a mixture of water and soap (a few drops of washing-up liquid will suffice). This allows the stickers to be easily moved and aligned until the liquid has dried. With a squeegee you can then „push out„ the remaining liquid and thus accelerate the drying process and reduce the formation of bubbles. Important: This tip does not work with motifs on transfer foil! Here you will find detailed instructions.
When gluing behind glass, you should note beforehand that your glass may be slightly coloured (e.g. blue cast) and the colours of the print may appear slightly different.
Please also take note of the information on the subject of shop window bonding for the suitability of the pane: PDF Download Federal Association or information from the film manufacturer.