Be familiar with the coding style and contributing guides.
Code (yours or others') must be reviewed publicly (by you or others) before you push it to the repository. With one exception (see below), every change needs at least one review.
If one or more people know an area of code particularly well, code that affects that area should ordinarily get a review from one of them.
The riskier, more subtle, or more complicated the change, the more careful the review required. When a change needs careful review, use good judgment regarding the quality of reviews. If a change adds 1000 lines of new code, and a review posted 5 minutes later says just "Looks good," then this is probably not a quality review.
(The size of a change is correlated with the amount of care needed in review, but it is not strictly tied to it. A search and replace across many files may not need much review, but one-line optimization changes can have widespread implications.)
Your own small changes to fix a recently broken build ("make") or tests ("make check"), that you believe to be visible to a large number of developers, may be checked in without review. If you are not sure, ask for review. If you do push a build fix without review, send the patch to ovs-dev afterward as usual, indicating in the email that you have already pushed it.
Regularly review submitted code in areas where you have expertise. Consider reviewing other code as well.
Do not push merge commits to the Git repository without prior discussion on ovs-dev.
If you apply a change (yours or another's) then it is your responsibility to handle any resulting problems, especially broken builds and other regressions. If it is someone else's change, then you can ask the original submitter to address it. Regardless, you need to ensure that the problem is fixed in a timely way. The definition of "timely" depends on the severity of the problem.
If a bug is present on master and other branches, fix it on master first, then backport the fix to other branches. Straightforward backports do not require additional review (beyond that for the fix on master).
Feature development should be done only on master. Occasionally it makes sense to add a feature to the most recent release branch, before the first actual release of that branch. These should be handled in the same way as bug fixes, that is, first implemented on master and then backported.
Keep the authorship of a commit clear by maintaining a correct list of "Signed-off-by:"s. If a confusing situation comes up, as it occasionally does, bring it up on the mailing list. If you explain the use of "Signed-off-by:" to a new developer, explain not just how but why, since the intended meaning of "Signed-off-by:" is more important than the syntax. As part of your explanation, quote or provide a URL to the Developer's Certificate of Origin in the contributing guide.
Use Reported-by: and Tested-by: tags in commit messages to indicate the source of a bug report.
Keep the AUTHORS file up to date.