Thanks for the reply Fuzzy, those links where very useful.
I've got my head around layers and gradients. I'm comfortable with creating a drop shadow and could work out how to create a lighting effect. What I'm struggling with is how to add a tinted and shaded edge to a basic shape. From the link above, in the section labelled 'Edge tint and shade', there are two images:
https://material-design.storage.googleapis.com/publish/material_v_4/material_ext_publish/0Bx4BSt6jniD7T21HZ3M4N3IwTDg/style_logos_product_lighting_edge_tinted.png
https://material-design.storage.googleapis.com/publish/material_v_4/material_ext_publish/0Bx4BSt6jniD7d0JqZl9BOUVYcHc/style_logos_product_lighting_edge_shaded.png
Which show you where the tinted and shaded edges should be. There are also some metrics in the table beneath the images, e.g. Height: 1dp Opacity: 20%, etc. First of all, how do I do this in paint.net? Is this as simple as drawing a line underneath and above the shape?
Secondly, the reference to which colour to use is confusing. The metric for color says 'Refer to Tint, shade and shadow values'. When I look at the colour chart is looks as follows:
https://material-design.storage.googleapis.com/publish/material_v_4/material_ext_publish/0Bx4BSt6jniD7ZGVnX1FaLTlYWVk/style_logos_product_lighting_values_neutral.png
What do the percentages mean? Is the chart basically saying, for example, if I chose a colour of Grey 200 (whatever that means) than the Tinted edge should contain 40% white and shaded edge should contain 10% Grey 900? If so, then again, how do I achieve this in paint.net?
Kind Regards