The steps below will add an extra DOT allias in your existing Email ID. Normally yahoo dont allow a dot-id as an profile. The new ID can be used as another alternative ID. The best thing is, you can log-in to your inbox using the same password. The inbox in both the IDs will be the same too.
Step 1: First of all open mail.yahoo.com and login there.
Step 2: Then copy the link below and paste it to the addressbar of the previously opened browser window. and press Enter.
Step 3: Then it will ask you to confirm your password. rite ur password there and click the button below.
Step 4: Then you will come to a page saying “Create an extra email address”. In the Left type in the dot name you want to use. click submit
Step 5: It will create a new Email account IF that name is available. Now when you go to your “Account Information”, you will see that dot name added to your alias.
This will only allow you to make ONE dot name per account. You will only be able to change this if you delete the old dot name and then make a new one.