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 the Shakespeare play "Much Ado About Nothing."