Compatible new Battery

Philipps 000 Screwdriver

Thin but firm piece of plastic for removing the top and the glue from the battery - I used a plastic card from a set of display protection foils, but it was a little small to reach all the glue under the battery. Also note that it will probably be pretty crumpled afterwards

A very small flathead screwdriver to pry open the top

A hair dryer (or heat gun, but do not use too hot settings or your phone might be damaged)

Some time - probably at least an hour - since you will need to unscrew everything in order to be able to safely remove the battery

To make things extra safe, discharge your phone's battery before opening it.