Regarding the outliner pencil that is included with some of the Inktense sets... the line drawn with this pencil did not prevent colors from running into each other on fabric. It may do this on paper, however.
Linda, it's good to try techniques. I colored and then added water to the background of an iris, and it didn't turn out dark enough. So I will have to work on that again. You might need to do that to your background, too, depending on the look you want. I usually like full color saturation...no white fabric showing unless it is supposed to be white.