To manage & fulfill Incentives you've offered through your campaign, head over to your campaign's Transactions page. Just click the word "Transactions" in your campaign's NavBar.
On the Transactions page, you'll be able to see the Incentive that was claimed, along with any information our Data Collection feature collected for you (mailing address, phone#, etc.). Click the plus sign (+) or the date over on the left side to see the Data Collection info.
You'll see a check mark next to the Incentive. Click the check mark to keep track of which Incentives you've already delivered.
A green check mark means you've fulfilled it, and a grey check mark means you haven't.
Note: If you'd rather use your own software or personal system to keep track of Incentive fulfillments, you can always download your campaign's transaction history (including everything you see on this page) into a XLS or CSV spreadsheet. Click here for more info.