The more people you will follow the more follow back you may find. So, increase following and get follow back. Once will follow someone make sure the pinner is similar to you. That means the Pinner divide related content to you.
From time to time we forget to put site link on images and description. In this state you have zero chance to get visitors from that pins. But I can see a great chance still if you have blog address on your profile. Visitors can come to your site by the link also. See bellow image for your easy accepting.
Click on your user name and Find friends from the dropdown menu. See bellow image for your easy recognize. Now you can see two options to invite your friends. At first find Facebook Friends then Find Twitter Friends and Follow them. As they are your friends in Facebook and Twitter so they may follow you on Pinterest too.