You have to use a photo hosting service like photobucket.com. Once you register and have an account (it's free) you upload your photos; then when you want to post a pic here, you go there,
select the one you want, copy the URL where it says "image" and paste it to your post here. You should also resize them to 640x480 before posting them here. I resize them before I load them to photobucket. I'm sure someone could explain it a little better than this, but it's pretty easy once you get it figured out. Good luck!