Using a powerful hair dryer or a heat gun, heat the earbud for about ten seconds to soften the glue that sticks both parts of the earbud together.

Careful: if you heat the earbud too much, the plastic shell may distort.

Heat the earbud all around.

This is a difficult step because you need to heat the earbud enough to soften the glue inside the earbud without burning the plastic of the earbud’s shell.