If other answer did not sort it, Could be the plug lead, get them cheap anywhere even from ebay. As other, swap plugs around, if misfire changes to different cylinder, plug fault, could just need cleaning and gap set. If it stays at same cylinder, I would go for lead first, coils are expensive. DO NOT swap leads around. severly damage your engine. If it managed to start at all.
Come off the sexist bit, Some very good female mechanics around
SD
October 2011