Most people are skeptical of UFO's until they see a bright light while driving alone some night and their car engine stops and the next thing they know they are waking up staring into the face of some blob with eyes like big watermelon seeds and then they feel something cold and tingly sliding into their rectum and for a brief moment they feel intense affection for Mr. watermelon seed eyes and then it's over and they are laying on the ground next to the car and they drive home and tell everyone why they disappeared for a day and a half and the damn fools are too stupid to understand the seriousness of what happened and even question the truthfulness of your story and what makes it all the more difficult to convince them is the bad case of crabs you have picked up.
This usually converts skeptics to believers.