Go to your Tumblr dashboard and click the gear icon to go to your Tumblr account’s Settings page. Pick the name of the blog you want to customize with an Ask link and page to go to its Settings screen. Click the “Let People Ask Questions” box in the Ask section to turn on the feature. Type a word or phrase for the Ask page link text, such as “Ask," “Messages,” “Ask Section” or “Ask me anything!,” in the “Ask Page Title” field. Scroll up to the top of the Settings screen, or down to the bottom, and click the “Save” button. Confirm the setup. Go to your Tumblr blog and look for the “Ask” page link. To see new questions, wait for a Messages Inbox alert in the form of a number to appear at the upper-right corner of the envelope icon on your Tumblr dashboard. Click the icon and look for any new message titled with the name of a user or the word “Anonymous,” followed by the words “asked you." Information in this article applies to Tumblr as of September 2013.
