You'll be able to select and purchase the paid plan of your choice after you've created your campaign and clicked "create and continue" at the bottom of the campaign creation form.
Once you've clicked that green button, you'll land on the checkout page. There, you can choose a paid plan, enter your credit card information, and submit your campaign.
After your campaign is approved: You'll be able to access the upgraded features. We'll send you a email confirmation when your campaign is approved, and you'll get clear instructions on next steps.