Add section on manual style to Writing Guidelines

Specifies when to link to the class reference.
Specifies how to style various kinds of text.

contributing/documentation/docs_writing_guidelines.rst

@@ -507,6 +507,119 @@ examples with the ``:kbd:`` tag left as-is for better visibility:
 - Press ``:kbd:`Space``` and hold the left mouse button to pan in the 2D editor.
 - Press ``:kbd:`Shift + Up Arrow``` to move the node upwards by 8 pixels.
 
+
+Manual style guidelines
+-----------------------
+
+Follow these formatting guidelines while writing documentation. Use your best judgement. 
+If you can write more clearly by ignoring these guidelines, do so.
+
+.. note:: Much of the existing manual does not follow these guidelines. You don't
+    have to go out of your way to change existing pages, but do try to bring
+    pages up to standards when you are already making changes.
+
+Text styles
+~~~~~~~~~~~
+
+There are a few styles that the manual uses.
+
+
++---------------------+--------------------------+------------------------------------------------------------------------+
+| Style               | RST formatting           | Typical usage                                                          |
++=====================+==========================+========================================================================+
+| Plaintext           | ``Plaintext``            | Used for most text.                                                    |
++---------------------+--------------------------+------------------------------------------------------------------------+
+| "Quotes"            | ``"Quotes"``             | Used for some literal or quoted values. In many cases, another         |
+|                     |                          | style is preferred.                                                    |
++---------------------+--------------------------+------------------------------------------------------------------------+
+| *Italics*           | ``*Italics*``            | Used for emphasis. Used for introducing new terms.                     |
++---------------------+--------------------------+------------------------------------------------------------------------+
+| **Bold**            | ``**Bold**``             | Used for emphasis, editor menus and windows,                           |
+|                     |                          | and editor navigation paths.                                           |
++---------------------+--------------------------+------------------------------------------------------------------------+
+| ``Code``            | `` Code ``               | Used for variable names, literal values, and code snippets. ``code`` is|
+|                     |                          | used in many cases where you would use "quoted plaintext" in typical   |
+|                     |                          | English.                                                               |
++---------------------+--------------------------+------------------------------------------------------------------------+
+
+
+Literals
+~~~~~~~~
+
+Literal values use ``code style``.
+
+- Ints: ``0``, ``2``, ``-5``, ``100``.
+- Often, floats include the decimal: ``0.0``, ``0.5``, ``2.0``, ``-5.0``, ``1000.0``.
+- Often, vectors include the decimal, and have a space between each field: ``(0.0, 0.0)``, ``(0.5, -0.5, 0.5)``, ``(1.0, 2.0, 3.0, 4.0)``.
+
+Classes, properties, and methods
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When discussing a class, link to the class reference the first time you mention it within a section.
+After the first mention of the class, do not link to the class reference. If the class is very common,
+like ``Node``, ``Node3D``, ``Control``, or ``Viewport``, you don't have to link. When discussing an instance of
+a class, do not link to the class reference.
+
+When mentioning a class property or method, link to the class reference the first time you mention it in a section.
+If the class member is very common, like a Node2D's ``position``, you don't have to link. Instead, either style as plaintext
+or ``code style``.
+
+Properties
+~~~~~~~~~~
+
+Properties are styled differently, depending on whether you are using the inspector
+or not.
+
+For properties in the inspector, use either ``code style`` or **bold style**, and
+use the name it appears in the inspector. If the property is nested within the
+inspector, use the full path.
+
+For properties being used in code example, link to the property the first time it
+is mentioned, then use ``code style``.
+
+Editor menus and windows
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Editor menus and windows use **bold style**. Plaintext is also okay, if it's more natural. 
+For example, use **bold style** when referring specifically to **Project Settings** window,
+but use plaintext when referring to the concept of project settings.
+
+**Good**:
+
+- **Editor Settings**
+- The **Editor Settings** window.
+
+Editor navigation paths
+^^^^^^^^^^^^^^^^^^^^^^^
+
+Editor navigation paths are used to describe a series of menus, submenus, actions,
+or buttons that the reader should follow. Navigation paths use **bold** style, 
+and use ``>``, ``->``, or ``→`` as a separator, with spaces on both sides.
+
+**Good**:
+
+- **Editor > Editor Settings > Shortcuts**
+
+**Okay**:
+
+- **Editor -> Editor Settings -> Shortcuts**
+- **Editor → Editor Settings → Shortcuts**
+
+Project settings
+~~~~~~~~~~~~~~~~
+
+Always link to project settings. Either include the full path of the setting in
+the link text, or specify the path and the link separately. The setting name
+should be ``Title Case``, as it appears in the project settings. The project
+setting navigation path is styled as **Bold > With > Arrows**.
+
+**Good**:
+
+- Set :ref:`Max FPS<class_ProjectSettings_property_application/run/max_fps>` in **Project Settings > Application > Run** to ``60``.
+- In **Project Settings > Application > Run**, set :ref:`Max FPS<class_ProjectSettings_property_application/run/max_fps>` to ``60``.
+- Set the :ref:`ProjectSettings > Application > Run Max FPS<class_ProjectSettings_property_application/run/max_fps>` project setting to ``60``.
+
+
 When to refer to a specific Godot version
 -----------------------------------------