instaGC is a site I discovered this summer from a friend of mine that's been using it for a long time. It is pretty user friendly interface with various tasks to complete for giftcards.
Though I have some pending points from July so I have a jump start towards my goal. One thing I think about this site is that you can customize goals to specific amounts in general to exact amounts for giftcards for your favorite store. Another aspect that I utilize is that you can change your goal if you want to lower it to get a card faster or to change let's say from Dunkin Donuts to Amazon or any other store.
Below in my referral link which I am grateful for anyone that uses it to sign up on the site as it will help me to reach my caffeine fix quicker :)