Frosted glass, otherwise known as privacy glass, is commonly used for bathroom windows, entrance door windows, etc. but not all windows come with the glass frosted.
Growing up I remember the film you put on the windows to make them frosted, but these days there are ways that allow you to get more creative than the film of the old days.
Glass frosting spray is the best for the creative DIYer. It comes in a variety of colors or you can get it in the standard clear. One way you can get creative when spraying glass frosting is to use tape to make a pattern on the glass before you spray it, and then carefully remove the tape before the frosting dries.
Another way is you can use stencils. Stencils sounds like more work, but it’s actually simple. First off, find a stencil you like (craft stores usually have a good variety). You can either have someone hold the stencil in place or you can tape it. Now this is an old painter's secret, so don’t tell anyone….
With the stencil in place, put some Vaseline on your finger and generously wipe it into the pattern of your stencil. Carefully remove the stencil and repeat for multiple applications. Be sure not to touch the area where you applied the Vaseline.
Spray the glass frosting and allow it to dry thoroughly. Once it dries, clean the glass and the frosting will wipe away where the Vaseline was (paint and sprays do not adhere to something that is coated with Vaseline).
Note: Be sure to tape off and/or cover any/all areas where you do not want the frosting. As with all sprays, there will be a lot of over spray. When frosting something that is indoors, it is advisable to cover an area about three feet (or more) surrounding the area you will be spraying.