All you need to do as the owner is to send a car key invitation link to the drivers from your phone. The drivers can then, through the invitation link, set up their own digital key.
Note
The digital key is currently available for iPhone and Apple Watch models compatible with the latest iOS and watchOS versions.
Visit the Apple website for more information https://support.apple.com/en-us/118271.
Sharing a digital key as the car owner
You can share a digital key via the Volvo EX30 mobile app and the Apple Wallet app.
Via the Volvo EX30 app:
Log in to the Volvo EX30 mobile app and go to the car tab 
> Digital key.
> Digital key.Press Manage digital key.
You'll be re-directed to the Apple Wallet app.
Press the share-button in the top-right corner.
Select the communication channel you would like to send the invitation link through.
Select key permissions and press Continue.
Authenticate yourself if required by the wallet app.
Select a person and send the invitation link.
A digital key is now shared.
Via the Apple Wallet app:
Open the Apple Wallet app on your phone.
Press on your digital key.
Press the share-button in the top-right corner.
Select the communication channel you would like to send the invitation link through.
Select key permissions and press Continue.
Authenticate yourself if required by the wallet app.
Select a person and send the invitation link.
A digital key is now shared.
Setting up a digital key as an additional driver
To proceed with the steps below, the person with an owner profile should have sent an invition link to you through a communication channel such as text message or email.
Press on the car key invitation link.
You'll be re-directed to the Apple Wallet app.
Press Add Car Key.
Press Done.
You digital key is now ready to use.
If you want to add your digital key to your Apple Watch, you can do so via the Apple Watch app on your iPhone. For more instructions, visit the Apple website https://support.apple.com/en-us/118271.
Applicable models
EX30, model year 2024 and later