To add a collaborator to your Microsoft Forms form, you’ll want to follow these steps:

1. Sign in to Microsoft Forms.
2. Open an existing form or create a new one.
3. Click Share, and enter the email address of the person you want to share the form with.
4. Choose the type of access you would like to give the collaborator (view, edit or respond only).
5. Click Send.

Your collaborator will now be added to your form and receive an email notification.