Guidelines for Creating a Good Pull Request - jonas-rem/RIOT GitHub Wiki

The title and initial description of a pull request (PR) should describe its basic idea and what goal is intended to be achieved in a brief and comprehensible manner.
Try your best to document how the provided code is intended to reach this goal. If the reviewer has difficulties to understand your approach, try to improve the documentation.
Keep pull requests as small as possible. The smaller a PR, the more likely it gets reviewed in short time.
Split your PR up into logical pieces. E.g. formatting changes or accompanying tests should go into separate commits.
Support your reviewer! Try to react as quick as possible to your reviewer's comments - and if only by letting her/him know, that you have currently no time to incorporate her/his feedback. Also, let the reviewer know if you do not plan to continue to work on a certain PR. Furthermore, if your reviewer don't react for some days, remind him!