You can mask your outgoing emails from Gmail in 5 easy steps:
1. Log in to your Gmail account.
2. Click Settings at the top of the page, and then select the Accounts tab.
3. Click Add another email address in the Send mail as section.
4. Enter your full name in the Name field, and the email address you’d like to send messages from in the Email address field.
*Keep in mind that each time someone replies to a message you send using a custom ’From:’ address, the reply will be delivered to the ’From:’ address rather than your Gmail address. If you’d like replies to be delivered to another account, you’ll need to enter a ’reply-to’ address. Just click Specify a different reply-to address to enter this information.
5. Click Next Step and then click Send Verification to complete the process. Gmail will send a verification message to your other email address to confirm that you’d like to add it to your Gmail account. You’ll need to click the link in that message, or enter the confirmation code in the Accounts section of your Gmail account, to complete the process. Once you’ve verified that you’d like to add the address to your account, you can start sending messages using your custom ’From:’ address.
Note: your Gmail address will still be included in your email headers in the sender field, to help prevent your mail from being marked as spam. Most email clients do not display the sender field, though some versions of Microsoft Outlook may display "From firstname.lastname@example.org on behalf of email@example.com."
Congratulations you have successfully masked your outgoing emails from your Gmail account!