Pull your knots either using the see-saw motion as advised by Yulitle in his video or you can use a roatating motion as advised by the UKRSA (basically achieves the same as Yulitle's method). Use a starting clamp for better grip or if you have to some very smoooth pliers! Also, release your clamp before you trim the tail - the last thing you want to do is trim the knot and have it come undone as you release the clamp and the knot beds in with the tension pulling back!
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I Shoot - www.flickr.com/photos/ashtennis guru/ (again no spaces! grrr)