一応、英語が母国語なのですが、以下の英訳で如何でしょうか。
"Proof my picture has travelled the world"
"I have taken a photo of myself with the picture I drew.
I am mailing the picture around the world.
If you receive the picture, please take a photo of yourself with the picture and e-mail me the photo.
You can hide your face if you don't want to show it.
I will post the two photos with your country and nickname on Facebook."
"Who I choose to send the photo to is completely random."
"The following people have a good chance of being chosen to receive the picture.
People who help out translating the site and e-mail in other languages.
People who live in countries I haven't sent the picture to before.
People who send a message that strikes a chord with myself and my daughter."
お礼
こんなに早くお答えをいただけて嬉しいです！ とっても助かります。 日本語も堪能でらっしゃるのですね。 あこがれてしまいます・・！(´∀｀) 本当にありがとうございました！