docs: add review tips (#46)

* docs: add review tips

Signed-off-by: Kenji Miyake <[email protected]>

* update .pages

Signed-off-by: Kenji Miyake <[email protected]>

docs/contributing/pull-request-guidelines/.pages

@@ -1,2 +1,3 @@
 nav:
   - index.md
+  - review-tips.md

docs/contributing/pull-request-guidelines/review-tips.md

@@ -0,0 +1,45 @@
+# Tips
+
+This page introduces tips around pull requests or reviews.
+
+## Toggle annotations or review comments in the diff view
+
+There will be some annotations or review comments in the diff view during your review.
+
+Press the `A` key to toggle annotations.
+
+Before:
+
+![before-press-a](images/before-press-a.png)
+
+After:
+
+![after-press-a](images/after-press-a.png)
+
+Also, press the `I` key to toggle review comments.
+
+Refer to [GitHub Docs](https://docs.github.com/en/get-started/using-github/keyboard-shortcuts) for other keyboard shortcuts.
+
+## View code in the web-based Visual Studio Code
+
+You can open `Visual Studio Code` from your browser to view code in a rich UI.
+Press the `.` key on any repository or pull request.
+
+Refer to [github/dev](https://github.com/github/dev) for more detailed usage.
+
+## Check out the branch of a pull request quickly
+
+If you want to check out the branch of a pull request, it's generally troublesome with the fork-and-pull model.
+
+```bash
+# Copy the user name and the fork URL.
+git remote add {user-name} {fork-url}
+git checkout {user-name}/{branch-name}
+git remote rm {user-name} # To clean up
+```
+
+Instead, you can use [GitHub CLI](https://cli.github.com/) to simplify the steps, just run `gh pr checkout {pr-number}`.
+
+You can copy the command from the top right of the pull request page.
+
+![gh-pr-checkout](images/gh-pr-checkout.png)