Howdy! I already activated user's signature.
Now, if you dont see your signature attached in your posts, probably you haven't organize your preference yet.
to do so, please follow this procedure.
1. Go to your Profile
2. Profile>Click Preferences
3. Preferences> look for "Always attach my signature :" then click Yes.
4. Go to your Signature and add your desire images as your signature!
Note: Read the signature Rules before doing so.