You insert the picture like you would with any regular image. Just click insert image, and then enter either the URL or browse for it in your documents. c:
Maybe use a lower quality gif in that case? http://ezgif.com/optimize
That website can reduce file size which should make the gif work, if it doesn't work after that I literally have no idea.
Or just don't attach it, use the
Where it says ''INSERT URL HERE'' you would put the url in. I don't know if it would work on your iPod so your best bet is trying on your computer.
It's 13.7kb, which is a lot. Try making the file size smaller by using that link I posted. http://ezgif.com/optimize