To expand the CRM Contact Management Portal for a Contact, go to CRM > Contacts > select the Edit arrow for the Contact > select the Expand Arrow in the activity and history section.
This will expand the Activity and History section to full screen. To return it to the former appearance, select the Retract Arrow.
Note: The Contact Portal will return to normal automatically when you move to a different page, so you will not need to retract it if you go to another contact.