Start by lining up your stencil on your phone case. Then, in a well-ventilated area, spray on the adhesive and allow to set according to instructions.
Remove the stencil and carefully lay the stick side of the phone case onto the copper foil sheet. Be sure to apply pressure to ensure full coverage of the foil.
Using an old paintbrush, wipe away the excess bits of foil. Keep in mind that the edges won’t be perfect!
You can also use washi tape to create patterns like stripes, plaids, and geometrics. Simply follow the same process.