How to keep certain areas the same color using magic wand

Hi! Okay so I'm VERY VERY new to recoloring (literally just learned like yesterday, lol) and I am using Paint.NET. I've been using the magic wand to select things and then the paint bucket to fill in the color, then multiplying the layer.... yadda yadda. So what I'm trying to figure out is how to keep certain parts of a mesh the same color? For example, I'm trying to recolor the basegame hightops and I can't figure out how to only color the shoe and while keeping the laces white. I know I have a lot to learn when it comes to recoloring, but I'll get there 

Thanks in advanced