Simple,go to Builders>Profile Fields. Click on Edit profile. Drag from Inactive Items the one called "NEW_ITEM" to the Active Items board. Create the block how you want it to appear and options.
Now click on View Profile (make sure you are looking at Owner options and not Admin). In that window you should see your newly created option block in the Inactive Items. Drag the newly created block to one of the headings for your view profile and the new block will show on your profile page with whatever text your members enter.
If the block isn't showing up on the profile page then you may need to add the Block (purple box) to the profile page. Click on Builders>Page Blocks. Select Profile from drop down. Drag the name of the inactive block that you placed you new item under (i.e. General, Misc, etc.) from the Inactive Blocks to your profile page. Now your new item will show up (only if data is in the block, if the block has options or is text input and no option or text is inputted, dolphin will not show the existence of the block ).