After you finish creating your email signature, click “Save and Install” button under the signature preview:
Or if you have saved your signature priorly, hover over your signature on the dashboard and click “Use” button.
Select the Gmail icon in the list of email clients.
Under the Signature preview click the Copy signature button, which will save the signature code in the clipboard.
Go to the lower left corner and click on the image of your account and then choose Settings:
Then choose Accounts, go to the account you need and paste your own signature there:
The last thing is to ensure it is saved:
And now it's time to send an email.
We are done!
Your signature is ready. Enjoy!