Remove the battery.

During reassembly:

Remove any remaining adhesive strips with tweezers or your fingers.

Clean up the adhesive residue with a few drops of isopropyl alcohol and a lint-free or microfiber cloth.

Before removing any adhesive liners, place the battery in its recess and make sure it fits.

If your replacement battery comes with adhesive, remove the plastic liners and firmly press each cell into place.

If your replacement battery doesn't come with adhesive, secure it with stretch-release adhesive.

Alternatively, you can use strong double-sided tape to secure the battery.