You simply click the 'Edit theme' icon on the top right of your logged in home page to open the edit side panel.
Look for the panels named:
Show tag dropdown - this turns the feature on and off
Tag dropdown items - add the tags you want featured making sure you add a '+' symbol between each like so 'bicycles+cars+go karts+trains'
Tag dropdown name - this is the word you want to appear in the navigation i.e 'Tags' or 'Categories' or 'Work'