index.html: corrected checkout command when submitting fixes

Until now, the part of 'index.html' that instructed how to submit
fixes incorrectly asked users to use 'git branch -b', but this should
have been 'git checkout -b'. Also, we didn't have a step to make sure
the local 'maneage' branch is up to date.

With this commit, both issues have been addressed.

This problem was reported by Faezeh Bidjarchian.

1 files changed, 4 insertions, 3 deletions

diff --git a/index.html b/index.html
index 82566e5..bf6471b 100644
--- a/index.html
+++ b/index.html
@@ -146,9 +146,10 @@ git checkout -b main                              <span class="comment"># Make n
                     Here is a summary:
                     </p>
                     <ol>
-                        <li>Go to the <code>maneage</code> branch and create a new branch from there like below:
-                            <pre><code>git checkout maneage
-git branch -b my-fix</code></pre>
+                        <li>Go to the <code>maneage</code> branch, make sure it is up to date, and create a new branch from there like below:
+                          <pre><code>git checkout maneage
+git pull origin-maneage
+git checkout -b my-fix</code></pre>
                         </li>
                         <li>Commit your fix over this new branch (see these <a href="https://www.gnu.org/software/gnuastro/manual/html_node/Commit-guidelines.html">commit message guidelines</a>).</li>
                         <li>Build a new project on your favorite Git repository (GitLab, BitBucket, or GitHub for example) and assign it to a new Git remote in your project.