Document class methods and dependency on PIL

README.md

@@ -44,3 +44,38 @@ If you're using the wHAT you'll need to load the InkyWHAT class from the Inky li
 from inky import InkyWHAT
 inkywhat = InkyWHAT('red')
 ```
+
+Once you've initialised Inky, there are only three methods you need to be concerned with:
+
+#### Set Image
+
+Set a PIL image, numpy array or list to Inky's internal buffer. The image dimensions should match the dimensiosn of the pHAT or wHAT you're using.
+
+```python
+inkyphat.set_image(image)
+```
+
+You should use `PIL` to create an image. `PIL` provides an `ImageDraw` module which allow you to draw text, lines and shapes over your image. See: https://pillow.readthedocs.io/en/stable/reference/ImageDraw.html
+
+#### Set Border
+
+Set the border colour of you pHAT or wHAT.
+
+```python
+inkyphat.set_border(colour)
+```
+
+`colour` should be one of `inky.RED`, `inky.YELLOW`, `inky.WHITE` or `inky.BLACK` with available colours depending on your diplay type.
+
+#### Update The Display
+
+Once you've prepared and set your image, and chosen a border colour, you can update your e-ink display with:
+
+```python
+inkyphat.show()
+```
+
+
+# Migrating
+
+If you're migrating code from the `inkyphat` library you'll find that much of the drawing and image manipulation functions have been removed from Inky. These functions were always supplied by PIL, and the recommended approach is to use PIL to create and prepare your image before setting it to Inky with `set_image()`.