Start by going to your “invite” page from your SaneBox menu. Copy the unique invite code link, specific to your SaneBox account. To do so, click the box area around the code. That makes a copy of your link to your clipboard, to paste it later. https://www.sanebox.com/invitations
Next steps from Yahoo web-mail
1.) From Yahoo web-mail, use the gear icon to access Settings.
2.) From there, select More Settings.
3.) Next choose the Writing Email tab, to the left.
4.) Finish by toggling on the Signature option, paste your invite link, and add a note.
If you have any questions - please reach out to us at support@sanebox.com!