I first came across this project in the late, great Mary Englebreit Home magazine. Basically all I did was buy an artificial wreath, spray it with fake snow, and then glue, wire or hang ornaments, sprigs of fake evergreen and holly, etc on it. I first began the wreath around 12 years ago and have added to it over time with more doodads. It's gotten pretty full by now; not sure if I can stick anything more on it!
Here's an overall picture:
Followed by several close-ups:
Most of the items date from the 1950's and 1960's, with a few things older or newer. Some of the ornaments are handmade, such as the felt snowman in the first close-up, and some are of the Made-in-Japan category, such as the elves. But what they all have in common is that they were purchased on the cheap.
A couple of years ago I made a similar style of wreath for a relative. I purchased everything I needed at one thrift store for about seven dollars total. It wasn't nearly as full as mine currently is, but I wanted to leave room for her to add her own elements if she chose to. It took all of about ten minutes to assemble. There's no right or wrong with this sort of craft!