Judy, I don't know if you knew this or not, but I thought I would tell you. You can add multiple signatures to your posts, by going to my home and then my profile and then add signature.
There you may modify your existing signature, or add a new one. If you would like more than two, you must repeat the process.
Once you have done this, when you finish typing in your post, scroll down a bit. There is a pull down menu where you can select which quote you would like to display.