Improve the contributing guide

CONTRIBUTING.rst

@@ -92,7 +92,7 @@ First time setup
 
     .. code-block:: text
 
-        git remote add fork https://github.com/{username}/click
+        $ git remote add fork https://github.com/{username}/click
 
 -   Create a virtualenv.
 
@@ -107,6 +107,12 @@ First time setup
 
         > env\Scripts\activate
 
+-   Upgrade pip and setuptools.
+
+    .. code-block:: text
+
+        $ python -m pip install --upgrade pip setuptools
+
 -   Install the development dependencies, then install Click in
     editable mode.
 
@@ -124,7 +130,7 @@ First time setup
 .. _username: https://docs.github.com/en/github/using-git/setting-your-username-in-git
 .. _email: https://docs.github.com/en/github/setting-up-and-managing-your-github-user-account/setting-your-commit-email-address
 .. _GitHub account: https://github.com/join
-.. _Fork: https://github.com/pallets/jinja/fork
+.. _Fork: https://github.com/pallets/click/fork
 .. _Clone: https://docs.github.com/en/github/getting-started-with-github/fork-a-repo#step-2-create-a-local-clone-of-your-fork
 
 
@@ -138,7 +144,7 @@ Start coding
     .. code-block:: text
 
         $ git fetch origin
-        $ git checkout -b your-branch-name origin/7.x
+        $ git checkout -b your-branch-name origin/8.0.x
 
     If you're submitting a feature addition or change, branch off of the
     "main" branch.