"Website verification establishes the link between a website and an account on Pinterest. Accounts with a verified website are denoted by a checkmark which displays next to their website on their profile page and below their name in search results."
Pinterest offers two ways of verifying your site - by HTML file upload or HTML meta tags. vFlyer sites currently supports the HTML meta tag option. Once you have copied your verification meta tag from Pinterest, you just need to put it on your site's homepage. For this just head to the Page Settings >> Search Settings and paste your meta tag into the Custom Meta-tags box.
Here is Pinterest's help page on verifying your site via meta-tag. You can find more info on editing your vFlyer Site's meta-tags here.