It is good training to trace line drawings, but if you want to take a shortcut and just apply color, or if you want to apply color to someone else’s line drawing you can use the Multiply blend mode.
First, open the (1) Layer Window, tap (2) Import Image and then select an image. Images with white parts that are very white are easier to work with and produce better results. If you are using an iPhone or iPad you can use the OS photo app to increase the brightness and contrast. You can also use any other app with similar functionality.
Next, place the image using a (1) one finger drag, and then set the size you want using (2) two fingers (pinch) to zoom in and out. Finally, tap the (3) End button.
Drag the transparent (1) Thumbnail (small image) above the image and then tap it to make it the Current Layer.
Tap part of the Layer Window which reads (1) Normal and change it to (2) Multiply from the list. This will change the Current Layer (the transparent layer) to Multiply mode.
Applying color to a Multiply layer creates a color which is made from the multiplication of the applied color and the color on the layer beneath it. If the lower color is black then the result will be black (as black is defined as 0, and 0 multiplied by 0 is 0). If the lower color is white then the color will not change (as white is defined as 1, and anything multiplied by 1 remains the same). In ibisPaint colors are given a number from 0-1 depending on their brightness. Multiplying a number by a number between 0 and 1 will produce a result which is either the same number or less than that number. This means that the result will be the same color or a darker color.
Simply put, the Multiply layer will be the brush color where the layer underneath is white and black where it is black.
Just splashing on colors is not that interesting, so try using a Pen (Soft) with a transparency set to 60% to make a watercolor pen effect. Only the cheeks were done with an airbrush.
The finished example looks like a hand drawn sketch that has been colored in. Doing it this way makes for a different feel to an all digital work.