Paint both sides of a seashell with acrylic paint. You'll be covering it with glitter, so as long as the the coverage looks decent, 1 coat of paint should be fine. Allow the paint to fully dry - about 1 hour.
Squeeze a fair bit of white glue onto the top of the seashell.
Using a paintbrush, spread out the glue so it evenly covers the entire top surface of the shell.
Step 2: Decorate with glitter and rhinestones
Sprinkle the fine glitter onto the wet glue so the surface of the seashell is fully covered. Allow the glue to dry for at least 1 hour then lift the seashell and tap off the excess glitter.
Squeeze more white glue onto the top half of the top of the seashell.
Again using a paintbrush, spread out the glue so that only the top half is covered with glue. Turn the paintbrush sideways and add some glue down into the grooves in the shell to make the glue line a bit uneven.
Press the rhinestones onto the wet glue.
Sprinkle the glue with the large glitter. Allow it to dry for at least 1 hour. Then lift up the seashell and tap off any excess glitter.
Step 3: Add the string
Cut a piece of string about 6 inches long and tie the two ends together into a knot.
Squeeze a small glob of hot glue from the glue gun onto the back of the seashell, then carefully press the knot in the string into the glue.