README - transition between modes (#127)

* README - transition between modes

* README code style

* README lint

* Reorganize new mode switching section and add link in mode description section

* Lint

* Change to <kbd> tags to address review comment

---------

Co-authored-by: firai <firai.admin@gmail.com>

README.md

@@ -26,6 +26,8 @@ This extension combines the Jupyterlab (Edit and Command) modes with the standar
    - Normal
    - Visual
 
+See [key bindings for switching between modes](#switching-between-modes).
+
 ## Install
 
 ```bash
@@ -103,6 +105,21 @@ Shortcuts this extension introduces:
 | Z, M    | Hide All Code Cells |
 | Z, R    | Show All Code Cells |
 
+### Switching between modes
+
+- From Command mode:
+  - To enter Normal mode from Command mode, press <kbd>Enter</kbd>.
+  - The extension blocks <kbd>Shift</kbd>+<kbd>Esc</kbd> from invoking browser commands, such as the browser task manager, by default. To disable the blocking behavior in Command mode, go to Settings menu → Settings Editor → Notebook Vim, and disable the "Override `Shift-Esc` browser shortcut in Jupyter Command mode" option.
+- From Normal mode:
+  - To leave Normal mode to Command mode, several options are available:
+    - <kbd>Shift</kbd>+<kbd>Esc</kbd>
+    - <kbd>Esc</kbd> or <kbd>Ctrl</kbd>+<kbd>[</kbd>, if the "Enable `Esc` and `Ctrl-[` leaving vim Normal mode to Jupyter Command mode" option is enabled (on by default). To disable the option, go to Settings menu → Settings Editor → Notebook Vim.
+  - To enter Insert mode from Normal mode, use one of the insert commmands, such as <kbd>i</kbd>, <kbd>I</kbd>, <kbd>a</kbd>, <kbd>A</kbd>, <kbd>o</kbd>, <kbd>O</kbd>, <kbd>c</kbd>, <kbd>C</kbd>, <kbd>s</kbd> or <kbd>S</kbd>.
+  - To enter Visual Mode from Normal mode, use one of the visual commands, such as <kbd>v</kbd>, <kbd>V</kbd> or <kbd>Ctrl</kbd>+<kbd>V</kbd>.
+- From Insert or Visual modes:
+  - To leave Insert or Visual modes to Normal Mode, press <kbd>Esc</kbd> or <kbd>Ctrl</kbd>+<kbd>[</kbd>.
+  - To leave Insert or Visual modes to Command Mode, press <kbd>Shift</kbd>+<kbd>Esc</kbd>.
+
 ## Special Thanks
 
 From @jwkvam: