This is how to add an additional stroke or fill in Adobe Illustrator. So sometimes we have a shape. Let's have a rectangle. We love rectangles. And we add a stroke to this rectangle. Let's say we increase the stroke size. Go to our stroke panel over on the right. If it's not there, we go to our window menu, and come down the stroke, click it, and it will open up on our right-hand side. We increase the stroke size. Now, let's say we want a blue stroke on this. We can do that, totally can do that. So what we have to do is, we have to then go to our appearance menu.
Let's minimize the stroke menu. So in our appearance menu you'll notice that you have the options to select your fill and select your stroke. So we're going to select a stroke and what we're going to do is, we're going to click the duplicate selective item option at the bottom of the window. Almost looks like the new layer icon. So we click that, and it will create a new layer, and it will have the same properties that our last item did. The only problem is, there's no way for us to see it. So we have to make the item that's underneath, because they are in stacking order, bigger than the one that's on top. And when we do that, that allows us to see the stroke that's behind that one.
So first let's change the stroke color. Let's change it to 100% Cyan, and as we start to bump it up you'll notice it starts to come from behind the black stroke. That's how you add an additional stroke. You can add additional fills the same way. All you have to do: you just select the fill, duplicate it in the appearance menu, and then you can change the fill that's on top. Now the benefit of that is, you can change that fill's blending mode. So it makes it real simple, you have this selected you can go to your transparency menu and the modes- the blending mode- is selected by a drop-down tab that's on the left part of your transparency menu. It's at the very top.
You can click that, and can change it to color dodge, and then it will knock out that color. You can change it to hue and then it will combine the hues of both yellow and the green. And just any number of things. Multiply will make the yellow darker using the green's hue, any number of things. So that is how you create multiple fills and strokes in Adobe Illustrator.