I have seen thousands of code reviews. A good code review happens when both the developer and the reviewer follow a productive etiquette:

• Always remember that code reviews are not competitions and shouldn’t turn into fights. Avoid being aggressive in your comments or responses. You work with the person on the other end.
• Be respectful in comments and responses. NO need for being aggressive or showing off, it won’t help.
• If some issues turned into arguments, it is better to chat in person. 

When you send your code for review, the following will help you get better feedback: 

• Provide a good context summary for your change.
• If you think that the comments show that the reviewer misunderstood something, politely indicate that. 
• Select the right reviewers who will give you the best feedback on the different dimensions.
• Keep the size of the changes as small as possible to make them easier to review. 
• If you have to send a large change, make sure to give the reviewers a warning and allow more time to respond. It will be even better to schedule a short meeting to walk the reviewers through the change.

When you receive a code review request, the following tips will help you give a good experience and share your feedback effectively with the developer:

• Evaluate the code on function, design, testing, and style. Don’t push the developer to rewrite the change to look as if you wrote it. There are multiple ways to express the same feature in code.
• Respond promptly to code review requests, preferably within a day. If a change is too large, respond in increments, and indicate that the response is a work in progress.