add notes on usage

doc/capability_templates/capabilities-template.jinja

@@ -20,6 +20,7 @@
 {{ escape_rst(printer.notes) }}
 
 You can select this profile in python-escpos with this identifier: ``{{ item }}``.
+(Set parameter to `profile='{{ item }}'`.)
 
 Basic information
 ^^^^^^^^^^^^^^^^^

doc/printer_profiles/available-profiles.rst

@@ -1,3 +1,5 @@
+.. _available-profiles:
+
 Available Profiles
 ------------------
 :Last Reviewed: 2023-07-27

doc/printer_profiles/capabilities.rst

@@ -6,6 +6,19 @@ Since the used command set often differs between printers,
 a model for supporting different printers is implemented.
 This feature is called `capabilities`.
 
-.. todo:: explain capabilities
-.. todo:: explain usage
-.. todo:: give hints on how to sideload and improve profiles (profile that is bundled with release can be replaced)
+The `capabilities`-feature allows this library to know
+which features are supported.
+If no further information is specified, python-escpos will
+try to automatically use features based on the supplied information.
+
+In order to use the `capabilities`-database, the printer instance
+simply has to be created with the parameter `profile` set to the
+relevant identifier.
+The identifier can be found in :ref:`available-profiles`.
+
+This documentation describes the profiles in the database file that
+is bundled with this release.
+If another configuration is to be used, this chapter can be followed
+for information on how to sideload another `capabilities`-database:
+:ref:`advanced-usage-change-capabilities-profile`.
+

doc/user/usage.rst

@@ -238,6 +238,8 @@ Here you can download an example, that will print a set of common barcodes:
 
     * :download:`barcode.bin </download/barcode.bin>` by `@mike42 <https://github.com/mike42>`_
 
+.. _advanced-usage-change-capabilities-profile:
+
 Advanced Usage: change capabilities-profile
 -------------------------------------------