You can use free online image host site like photobucket to upload your pictures to
http://photobucket.com/
once you've created an account, you can upload your pictures:
on the right side of your "my album" page
click browse
locate the picture and select it
hit open
and repeat for each picture if you have a couple more
then click "upload"
once it's been uploaded, you can click the box underneath your photo that says "IMG code"
that automatically copies the url.
then when you go to create a message here, just paste ( ctrl v) into your message and you're set!
thing is, it's helpful to resize your photo to maybe 500 megapixels before you upload so the image isn't so big. programs like picasa is real easy for that.
good luck and i hope that was clear!