The secret boards now allow you to showcase ideas and images in private to those who you wish. You are allowed to create up to 3 secret boards, however you can be invited to others secret boards without having any effect on your limit.
First way to create a secret board
1. Click Add+ at the top right-hand toolbar on Pinterest
2. Select Create a Board
3. Give your board a name, say who can pin, toggle the Secret setting to ON. This makes your board secret.
Second way to create a secret board
1. On the secret board’s settings page, go to the section titled “Who can pin?”
2. Type in the first and last name of the person you would like to add as a contributor or type in their email address. You can invite people you follow on Pinterest and your Facebook friends too.
3. Potential matches to this name will begin to load; when you see the person you want, click their name.
4. Click Invite.