Someone who makes a lot of ado about things has a tendency to make them more busy or complicated than they need to be.
A flurry of activity or a lot of complaining about a little problem are both examples of ado. It's an old fashioned word, dating back to the fourteenth century, when it meant "conflict or trouble." "At do" was a Norse version of the English phrase "to do," which was eventually shortened to ado. The most famous use of the word is probably in the title of Shakespeare's Much Ado About Nothing.