Log in to your account, hover over the gear icon and choose Settings.
In the Settings tab, select Filters from the left menu and click on the button to Add a filter.
Type a name for your filter in the Filter name field. Select contains in the sender drop-down menu. Type the sender's email address in the sender text field. In the Move to Folder drop-down menu, select Inbox. Click the on the Save button in the top bar to save the filter.