EDIT If this thing is showing up halfway down the damn page for you (like it is me) then just click the image and it returns to small-view and the page rights itself. I have no idea why it's doing this. dA sucks.
Greyscale method - traditional style!
(AKA Grisaille painting with overlaid colour glazes, in oil paints)
1: Toning the canvas - I graduated from pale to mid grey, bottom to top, using a mix of white and Payne's grey.
2: Painting straight in with rough forms, whilst the first grey layer is still wet. Still using only Payne's grey lightened with a little white...
3: ...followed immediately after with some shading, using soft darks and lights (not too contrasty - if you go too dark, the colour glazes will not work). Also took the opportunity to obliterate that ugly branch while the paint was still wet.
4: Once this had all dried, I added final darks and lights - still being careful not to add too much on the dark side of things. You want to be left with an image that looks like it's had the contrast turned down a bit in Photoshop. Also, stick to your monochrome palette. I like to use Payne's grey because it's not derived from straight black - it has a bluish-purple undertone to it.
5: Adding colour glazes. This is done by using a little Liquin to the paint to make it a bit transparent. You don't have to use Liquin if you don't wish to (it can create problems if not used correctly) - you can just apply straight paint very thinly. And make sure to wait til the underpainting is very much touch-dry before you add the colours!
You can also add more details and sharpen up the lights and darks if you wish. (I did.)
Hope it's helpful and whatnot.
Final painting: [link]