Here's a new tutorial from me. I use Adobe Photoshop CS2 version for colouring, but any versions is good anyway.
I tried to seek the terms translations as my version is in French, and couldn't find them all. But you'll just have to see the screencaps to know where to go etc.
Original picture from Katenka's DeviantArt Stock.

You first need the picture mode set on RGB. Then turn the picture to B&W. You don’t have to, but colours will look better on the picture if you do so. After that, use Auto levels to change the contrast and luminosity if necessary. It makes the picture look “clearer”.


Create all the layers you will need for any part of the picture. (Background, clothes, skin, hair, etc.).

Now we can start the colouring, I always start with the background. Go to the layer attributed to it, you can either select the area you want to colour or use the brush (in normal mode with 100% of opacity). Change the layer mode to soft light first, this way you could see through the colour how it looks. Then, of course, you can change the opacity and the mode of the layer to what you want and what you think looks good. =) If the colour doesn’t please you, you can use Brightness or Color Balance to change it. I finally chose colour burn mode with a low opacity for the background.

Next come the clothes, the details and the hair. I usually use Multiply, Colour Burn or Soft light for the hair.


Then comes the skin. Especially for it, I use colour mode with a pale colour with a opacity around 65-70 %. If you have hard time finding a good colour for the skin, you may try this code colour which I use most of the time: f4e7e0
On this very layer, colour the lips and cheeks with a light pink. Pick the brush in the Colour burn mode with a opacity of 70% to colour the lips, and for the cheeks, use multiply with a low opacity of 20%.


After that, colour the eyes on, of course, its own layer. Now that you finished colouring the picture, comes another thing. For giving a glossy and smooth effect on the skin, hair and clothes, use the smudge tool. You must use it carefully enough not to ruin the picture.


Now, that the picture is coloured and that I find it pale and liveless, I play with the contrast, opacity and layers… For this step, it is as you feel it

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And here’s the final result. Not that good.

I'm sorry if my explanations were blurry. But if you have any questions, feel free to ask.