Before you can start sending emails from SN as if it's coming from your email address, you will need to first connect your SN account with your email host.
If your email host is Microsoft (Office365, outlook.com, hotmail.com, live.com), Yahoo Mail, Zoho Mail, AOL Mail or Apple Mail (mac.com, me.com), you will need to choose the "SMTP Server" option from Email Settings.
To start connecting:
Go to Settings
Click Email Settings
Under "SMTP Server", click Connect.
A popup called "SMTP Server Settings" will appear.
Fill out the form fields. For the "Password" field, you will need to generate a one-time app password, instead of using your regular email login password.
How to generate app password
Please select your email host provider below and follow the instructions listed on each of their websites:
Once your email has been connected successfully via SMTP server, you will see a success message in the top right corner and be redirected back to Email Settings.