The layers printing feature is a excellent way to save ink and keep nested patterns from being too confusing to follow the lines well. This feature allows you to print only the sizes that you want or need to print. For example, you could print only the size large if that is the size you need or the sizes that you need to blend instead of printing all of the lines you don't need.
To do this, you will need to open your pattern in the latest version of Adobe Acrobat Reader and click on the stack of paper looking icon on the left side of the screen. This is the Layers Tab. This will open file and you can click the + sign next to it if it is not already opened in list form. The list will include all the layers that are available to view. Each size and a few layers that need to be always turned on are visible. There is an eye icon on the left side of each layer. To turn off the layer, simply click the eye and it will remove that layer from the pattern. Keep the sizes checked that you need and always keep all the layers that say KEEP CHECKED turned on.
Now you are ready to print. Print according to the printing instructions in the pattern as some vary.
Here is a short video to show you how to use the layers feature: