How to (UNFOLLOW) to no longer receive tweets / text messages on your phone:
If, in the future, you would like to no longer receive updates, please do the same steps as listed above except you will type UNFOLLOW rather than FOLLOW.
IMPORTANT TO NOTE:
If you are signing up via text and have a signature, it will not work. You will either have to sign up on twitter.com or remove your signature and then complete the steps above.