Question:

先に僕の写真を送っておきます。

僕の顔は多分、picoのと似てると思うんだけど・・・

本メールはまた今度ね

Um, I kind of have an Idea of what it means, but... Not very clear for me.

Answer:

"Let me send you my photo(s) first.
I might look like Pico('s)...
I am sending you (real) e-mail later."

fyi:I am a Japanese living in Japan.
TKX