Edit a New Inbox Rule
Outlook Web App should bring you to a page called new inbox rule.

You can automatically move E-mail based on:
Who it was received from
Who it was sent to
Or it includes specific words in the subject

5. Try It: Edit a New Inbox Rule
Name: Important

When the message arrives, select:
It includes specific words in the subject

Keep going...

Outlook->Inbox->Right-click->Create Rule