This sounds like the sort of question people get set for homework

Check out the documentation for String.  Using length() and charAt() you can iterate over a string and extract its constituent letters.  Pop these into an array and you're pretty much there...

i keep getting the following error: "This method must return a result of type String."

Post your code: the error message is meaningless without it; though I suspect you've tried to return the reversed array of chars without converting back to a String.  In which case check the String example ;)