Ask HN: How do you perform code review?

Hi.<p>As a developer, I know the importance of code reviews and I would like to be better at it. I have been working in different companies and I could see that there was not a consistent approach with it.<p>I could see different behaviors that code reviewers do, such as: - Leaving comments in a commit or a pull request - Leaving comments in their task tool (e.g. Jira, Trello) - Making the code review in isolation - Making the code review with the developer that made the changes - Making the code review with another developer that did not touch that code - Gathering multiple people in a room and letting the developer to walk through their changes. - Printing the code on paper (yes, I have also seen that..) - Strict code review - Soft code review, always accepting it<p>I know that there is not a unique way to do it,and you should use common sense in different cases but I was curious to know how do people in HN perform code reviews, what are your best practices(and why), what is the worse code review that you have received and what is the best one.