I made our chandelier (can you even call our boring light that?) into a Christmas tree! It's crazy easy, and works pretty much on any hanging light. I also did this in our house in South Carolina and the fixture was one with arms, so I know it works on those! :)
This is super easy! What you need is a wreath large enough to fit around the bottom of your light fixture. Or if you have one with arms, I just tied it on using ribbon.
I use a combination of garlands. I have a larger more expensive one....and I use the cheap dollar store ones as filler. Maybe after this season I'll purchase another nicer one. I think it'd make my Christmas Tree Chandy look even better! Take the nicer garland first and snake it around your light fixture. Use one of the small branches to secure it to the very top.
Then fill in the open areas with your other garlands. Use the branches from the first garland to secure these garlands in place.