Here are all tools that you might need for a successful battery replacement. Not all of them are necessary, but some of them are must. Must have tools are:

Optional tools are nice to have, but if you don’t have them there is no need to buy them:

I started by removing the strap with the strap removal tool and shroud by unscrewing 6 phillips head screws on the side of the watch. The watch was full of gunk from the wearing it so I washed it with dishwasher soap and warm water first.

The next step is to unscrew 4 phillips head screws on the back of the watch.