Access the Campaigns Page by clicking on the Campaigns link in the left-hand menu. Locate the campaign you wish to day part and click on the Campaign Name to open the Campaign.
Next, click the Edit button in the top right corner to open the Edit Campaign page
In the Schedule Section, click the +Add New button twice to create two new rows. In the first row, set the appropriate Day and Hour/Minute for when you want your campaign to run, and select Enable Campaign from the Actions drop down.
In the second row, select the Day and Hour/Minute of when you want your campaign disabled, and then select Disable Campaign from the Actions menu.
Once you have set the schedule, scroll to the bottom and click Save. Your Campaign will now only run during the time set per this schedule.
*If you have any schedules in the source portal, please disable them, as they can cause errors.