You can post your photos as attachments. To do that, you need to go to manage attachments when you make a new thread, or if you are posting in a thread, you can go to the Go Advanced option. There you'll find the option Manage Attachments. Click on that and attach your photos. Sometimes there are size problems, so you'll need to resize your photos so it can be attached. You can go to this website to resize your pictures
http://www.shrinkpictures.com/
Another way you can share photos is by using websites such as imageshack.com or photobucket.com
Basically you can sign up in these websites, and then manage your photos. I'm not sure about photobucket, if you can use it without signing up for it. But at imageshack, you can use it without signing up. So you upload your photo from the computer on the website. Then you will have a URL for your photo. You right click on your photo to get the URL. Copy URL. Then come here and you see this
(insert image), you paste the URL in here, but before you do that, you have to remove the http:// and then you paste the URL. Your photo should show up then. It's easier this way, if you find problems with attaching your photos.
Note: In sites such as photobucket.com (I'm not sure about the rest), others are able to view your photos from your account.