What you need:
window cling paint,
film/foil (e.g. sheet protector)
There are various kinds of window cling paint/window color.
With most of them, it is no problem to use them in combination.
Outliner paint is usually thicker than window
Window color is applied onto film or foil.
You can use sheet protectors because they are cheaper than window
A second advantage is that you can insert your painting pattern into the sheet protector and it will not slip while you are painting.
Insert the painting pattern into the sheet protector.
Before you start painting, shake the outliner paint.
Then draw along the outline of the picture. Probably you'll need to get used to painting with window
Try to use the bottle like a pen and work with constant pressure.
The outline you draw should not have any interruptions.
Let the outliner paint dry for some hours.
Before you use the window color, shake it as well.
Apply the paint evenly onto the film and spread it into every corner.
The window color needs to touch the outliner paint.
If you apply the paint too thinly, holes might develop when the paint dries because the paint shrivels up a little.
On the other hand, do not apply the paint too thickly because then light cannot shine through the paint anymore.
Let the picture dry for a day.
Carefully remove one corner of the picture from the film,
then take off the whole picture.
Press the picture to the window with the side that was on the film before. The picture sticks to the window by itself, you do not need any glue.
clings stick to glass, mirrors, tiles, and many other flat surfaces. Nevertheless, you should be careful when applying window
clings to wooden furniture because they might not be removed completely. If you cannot remove the pictures easily, try to soak them with water and washing-up liquid.