How do I perform a Ryobi trimmer string replacement?

To perform a Ryobi trimmer string replacement, first turn off the trimmer and disconnect the spark plug. Remove the spool cover and take out the old string spool. Cut a new piece of trimmer line to the appropriate length and insert it into the spool. Wind the new line evenly onto the spool in the direction indicated on the spool. Reassemble the trimmer and test the new string before use.