Assuming you would like instructions on how to string a head trimmer:
To string a head trimmer, start by threading the line through the eyelet at the bottom of the trimmer head. Then, pull the line through the center hole in the spool and wrap it around the spool a few times. Next, insert the end of the line into one of the notches on the side of the spool and pull it tight. Finally, repeat this process on the other side of the spool.