Hi, Kat. You can have a quote in your signature that will appear on every post, but Craig has temporarily disabled any pictures for the time being.
1. After you sign in with your user name and password, click on User-CP under "Welcome".
2. On the left side of your screen, under Control Panel, click "Edit Signature".
3. Type in the box what you want your quote to say, then click "Save Signature" underneath when you're finished.
Et voila! Your signature should now appear in every post until you change it. If it doesn't work, let us know and one of us can do it for you.
Good luck!