How to make a DIY bokeh filter

I have a new photography skill I want to share with you. This morning I tweeted:

So what is bokeh? Bokeh is the blurred, out of focus effect in the background of a photo when you shoot with a short depth of field.

And how do you pronounce it? I've read it originated from the Japanese language (boke) which means it's pronounced bow-kay. ETA: Hubby just suggested this is confusing because bow can sound like bow tie or bow wow. It's pronounced like bow tie.

Here are two examples of bokeh taken from my couch. Note how the white Christmas lights are soft and blurred instead of clearly defined.

But there's also something called a bokeh filter. It's where you have a circular shaped filter with a cutout in the center. The light passes through the cutout and any out of focus light source reproduces the shape of the cutout in the filter. Here's an example of how I made a bokeh filter, and a paper tube to hold it in place:

1. Take a piece of black construction paper and cut a circle the same size as the end of your lens.
2. I used an X-acto knife to cut out the tree shape. Or use a small paper punch shape like the kind used for making die cuts for scrapbooking. 
3. I cut out my shape from a smaller piece.
4. I then cut out the center of the circle and positioned and taped the cutout section into place using Scotch tape to keep it centered.
5. I wrapped some of the construction paper around the lens and used Scotch tape to hold it in place using the tension of wrapping it tightly to the lens.
6. I took the cutout section and slipped it into the end of the tube aligning the cutout against the lens.
7. Set your camera on the widest/largest aperture setting you can. I set my macro lens at 2.8 then used auto focus on something in the foreground so that the lights behind it took on the bokeh effect. I could have used manual focus to do this as well but the paper tube prohibited my ability to use my manual focus ring.

Does that make sense?

Here's a picture of the paper bokeh I made.

It nestled into place by tucking it into the paper tube around the lens.

It made Christmas lights like this. . .

Look like this!