Glad you asked...
All weed-eaters or a weed wacker work differently. The basics of threading it are first removing the bottom and threading the line through the head in the direction of the arrows on it tightly. Then thread the line through the eye making sure to leave 6" out so that it will feed the right way. Place the head back on tight and you should be able to start weed-eating.
kiraleta     How-To Expert
Then again, this answer might help you...
First don't be intimidated. Rethreading a weed whacker, or weed eater is not as complicated as you might think it is. It operates in a similar fashion to a fishing reel. You remove the cover, O ring and rethread your line.
nickeeninetails     How-To Expert
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