Ahh, this is an easy one. Thank you! Just click the down-arrow at the end of the “From:” field when you’re composing a message. Your other address should show up there! Click it.

And if you want to send from that address and get replies here in your Yahoo! account, here’s how:

1. Click Options in the upper-right corner of the page and select Mail Options.
2. Under “Management”, click Mail Addresses.
3. Click the address you’d like to adjust settings for.
4. Click Edit.
5. In the first section of the page that opens – “Sending Mail” – type the address where you’d like to receive Replies in the box after “Reply To:”. If it’s your Yahoo! Mail address for the account you’re currently in, type that.
6. At the bottom of the page, click Save Changes. Now you can send from that other address but still get replies to those messages here in your Yahoo! Mail inbox. Skillful!