Watch - Add item

First, you must install oneSafe on your Apple Watch. 
To do so, go to the apple watch app. 
You will find oneSafe under the section available apps: Install it.

Once the app is installed on your watch (it may take some time), open oneSafe and go in the setting tab. 
You must see a dedicated entry related to your watch. 
Setup a “watch password”. You must be ready to go.