How can I arrange my incoming email in alphabetical order?

I have done this by mistake. It has helped me to do a group delete. I find nothing to help me to do this again.
How can I arrange my incoming email in alphabetical order?
Just click on sender tab!
Reply:Open options on mail page and enter contacts. Set it to veiw all.
Reply:On Regular Yahoo! Mail:


1) Click "Subject" (in between "sender" and "date", sorta underneith "move")





On Yahoo! Mail Beta:


1)Click "Subject" (in between "from" and "date", underneith "print" and "spam")