3 yr old tantrums getting worse

We are just beginning our TSG journey and our 3 yr old is really getting out of congtrol with loud screaming tantrums over anything. "I wanted to do it myself", etc. We talk to her about "No" answers, and she seems to listen, but she really just can't seem to take a "no" answer, especially when she is tired. She likes the book Porter earns a quarter, and we talk about the lesson his grandpa teaches him, but when she gets so out of control from a "No" answer she just is not reasonable, and she can go on for a very long time tantruming. The more try to teach her, the more she escalates the tantrums. Help.