Well, what I do is first write the problem vertically. I'm going to make an example of 21 times 16. You see the 1 in the 21 and the 6 in 16? Multiply that and place it below your expression.Then you multiply 20 x 6 because you must add a 0 into the number since it is in the tens place and do the same and place it below. Then do it the other way across, 10 x 1 equals 10, place it below. Lastly, multiply the 2 tens place digits, 20 times 10, and place it below.Add up all your numbers below, and you will get your final product. Sorry if this confuses you.