After reading the reviews of your article, put them down and think for a day or so before crafting your responses. Sleep on it. Your immediate response to critical reviews might be anger or frustration, and you don't want these feelings to come across in your responses.
Provide point-by-point replies to each of the reviewers' comments. Indicate whether or how you changed your article to address each of the comments.
The tone of your responses should be polite and conciliatory, not antagonistic or subservient. If you disagree with a reviewer, provide solid reasoning behind your disagreement.
Keep your respones as brief as possible. Shorter responses convey that the comment was easily addressed and does not present a major problem.
If a reviewer was confused or mistaken about something in your article, this suggests that this part of the article needs to be written differently or more clearly. If the reviewer was confused, then other readers might be confused, too!