How do I install these decals?
Pick a good hard surface.
Clean the area of all debris and dirt.
Dry area thoroughly with clean cloth or paper towel.
Peel of wax paper type backing, leaving the sticker on the application paper.
If any pieces get left behind press firmly back down and peel again.
Apply to clean area.
Squeegee backing paper with a credit card or other smooth object working the entire sticker.
Peel application tape back on itself leaving the sticker behind,
Can these be removed?
Yes. Most can be peeled off if you can get an edge started, depending on how long they have been on a surface.
Some may require a razor blade or scraper to be used on glass.
Clean any remaining residue with appropriate cleaner for the surface.