Lots of people stop by my blog each day to find information about American English intonation patterns.
Here in the U.S. we use several types of intonation patterns when we speak. These include; rising-falling intonation, rising intonation, continuation rise, series intonation and tag question intonation.
In order to use intonation patterns correctly, you need to: learn the rules, identify the patterns, and listen for the patterns when others are speaking.
You also need to practice them aloud and get some feedback.
The most effective way to learn about intonation patterns is to get some accent reduction training with an accent reduction coach.
Another, less expensive way is to sign up for an accent reduction course.
Here is a great (and very affordable) video course that will teach you to use American English intonation patterns.