I took some pictures of my teacher manual of the three methods of addition we taught the students. They are: New Groups Above (this is most common in U.S.), New Groups Below, and Show All Totals.
My students have gravitated with New Groups Above mostly. This is the one I am most comfortable with as well. New Groups Below is almost the exact same as New Groups Above, except your put your "new group number" on the equation line instead of above the place value (see picture, it will make more sense). Show All Totals is adding in expanded form. This is helpful for students to "see" the new groups happening. We also create Proof Pictures to prove the addition happened with place value drawings.