I don't have an ipad, so I don't know if those upload differently, but from my laptop I went to tinypic, uploaded the photo, resized it to either "Thumbnail" or "Website/Email" (I can't remember which), then pasted the link into the signature box in my profile.
Hopefully, someone with more technological knowledge than me (which would be pretty much everyone) will have tips on how to get your signature pic up. I certainly look forward to more pictures of your C and R.