I will show you how I work with using effects in Adjustment Layers. To have an Adjustment layer, I right clicked on the Timeline panel and a list pops up. Inside that list there is a New option, I hovered over that option and it reveals another list. There, is the Adjustment Layer button, once I have selected that, it appears on top of the layers of the Composition. Whatever is above the Adjustment layer will not be affected, Whatever is below will be affected.
I am going to demonstrate what I mean in the stained glass composition. Down in the second image that I uploaded are the layers for each picture on the first image,
Now, where I circled in a light blue is the Adjustment layer that is going to effect the second top image of this page. The effect that I chose in the Adjustment layer is called the CC Cross Blur. Like in the name, it blurs horizontally and vertically across the screen.
Notice how the layer on top of the Adjustment layer was not affected at all. This is what I meant in the beginning of this Module.