Yarn in three colors (I choose monochromatic)
Large serving fork
Start wrapping yarn around the fork in your first color
When you've wrapped it around about 50 times or so, cut a small piece of yarn, string it through the fork and tie it once at the top
Pull the yarn off the fork and tighten the knot at tight as you can, making a second knot to reinforce
With your scissors, cut through all the loops on both sides
Fluff the yarn around the sides and trim if needed. Make several more; I made 5 in each color for my garland.
Take your needle (I used a large embroidery one) and thread it through one color of yarn. Using yarn to string the pom poms help as opposed to string helps keep them from moving around too much on the garland.
Using the threaded needle, string the pom poms together spacing them a few inches apart and alterating colors.
Hang with tape at your next party!