Template is not the correct word,( in french they call pochoir) stencil is the correct word, the technique is similar, only a bit more modern, using a three layer sticker,
first you have to remove the protection layer and than apply the sticker on the surface , push hard in order to obtain a good adherence of the sticker , than remove the protection film and finaly paint the letters, once the paint is dry , remove the remaining sticker;
Please see this film attached: