Helpful Hints
To get lines you can't color over:
In Photoshop: Duplicate your lineart layer. Set the top one to Multiply. Sandwich your color layers in between the two. You can delete the bottom one if you like, or put your background on it.
In Painter: Set your color layers to Multiply.
In Macromedia Fireworks, select the layer, and from the effects menu in the properties panel, select "other," and then "Convert to Alpha." Lock the layer, make all new layers/folders underneath it. Voila!
NEVER EVER USE THE DODGE/BURN TOOLS.
This is perhaps the biggest "newbie colorist" mistake one can make. How the dodge/burn tools work is by adding more black (burn) or white (dodge) to your color, making it less saturated and making your picture (especially skin) look very "dirty". Instead of relying on these, use your color palette to good advantage and choose colors with more saturation for your highlights and shadows. A good trick is to slip a bit of another color into them. For example, pinkish highlights look awesome on purple, while bluer shadows look great on green. Play around, see what you get.
an exception to this rule is when you are using greyscale, or something that won't suffer from the "dirty" effect, or if you are using only the dodge tool to make something look very shiny.
