Click “Actions” on the right side of the relevant campaign.
From here click “Custom segments”.
Select the wanted custom segments by checking the boxes. You can choose up to 5 custom segments to track with your campaign at the same time. However you may change the selected segments while the campaign is running if you need to.
Now the custom segments have been added to your campaign. To view them, click the “Profile” tab, and scroll to the bottom. Here you will be able to see specific data for each segment.