That size should last awhile. That's equivalent to a 20 long which is the absolute minimum for an adult ball python. You'll want to increase to at least 36 inches in length.
To post pics you first have to find a site to host them - somewhere where you can set up a photo album online. Kingsnake has a photo gallery section, and you can upload photos for free - up to a point. Once they're uploaded on a site, then when you are creating a post you can select an image from your photo gallery to attach (this option is available above the "Post message" button). Or you can insert multiple pics in a message. I haven't done that yet, but just click on the "Tools and Toys" link below the message box.
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Check Out My Albums
1.0 Ball Python
"Aragorn"
1.0 Kenyan Sand Boa
"Gimli"
0.1 Australian Cattle Dog/Pointer
"Kira"