I separate them to make a smaller Bush. But you could use the three pieces all together for a full one.
Cut the twine to what ever length you want. Leave space at the bottom for planting into the layout.Push down on top the the twine and spread the fibers out Until you get what looks like a bush.
Then add the tacky glue around the piece. This will hold it together during the process. It you don't they will fall apart. I know this from experience, let it dry over night. After it has dried you can push it out again to get the desired look.
Then you spray it with the spray paint. Put a good coating on this is what the static grass will adhere to.
Then take the 12mm static grass a pinch in between your fingers and sprinkle it over the bush.
Then spray it again with the spray paint .
Now take your scale leaves and sprinkle them over the top .Then I turn it over and do some from the bottom.Next I spray it with hairspray and set aside to dry overnight. I have found without the hairspray I lose a lot of leaves. When planting I trim it close to the Bush itself and make a hole and use the tacky glue to set it.
You can make them as big or small as you like. This is up against a fence to give you an idea of height.