Did you know that it's illegal to collect songbird nests? True. I'm not sure why this rule came into being because most often, migratory birds won't re-use an old nest (could it be they know about parasites overwintering in them?)
So to satisfy that rule, I developed my own faux birds nest, which is just as appealing, and doesn't have any bugs in it as an added bonus.
It also looks very realistic to humans, although a bird probably could tell the difference.
Here's how I started; with a piece of wire about 12-16" long, I twist it into a circle (see the full tutorial in the link above). Roughly speaking.
Then I took some flexible twigs, in this case Sheperdia canadensis, otherwise known as Buffaloberry or soopolallie, and wound those around the wire.
These worked well, as they are very flexible - test out any other type of twig you want to make sure they don't just snap and break when bent into the small circle. Those type of twig won't work for this. Stick with some willow twigs, maybe Amelanchier.
Birch and many fruit wood twigs won't be easily bent without the aid of steam or heat.
The point here is to make a kind of bowl shape, and neatness doesn't count. Just the general shape is fine.
Then I put some Spanish moss from the dollar store in a pile in the middle and hollowed out the center, just like a real nest.
I have some tiny wrens eggs (also from the dollar store), which are turned wood pieces. Of course, they are hidden away in my craft storage cabinet and I can't find them, so I went with plan B:
Oval beads with some strips of newspaper to be papier mache - leave them rustic!
Smudged with some acrylic craft paint, they resemble real songbird eggs.
Tiny lengths of very fine wire to thread through the hole in the bead, then attached to the nest makes them secure.
Display your tiny nest under a glass cloche with a rustic twig - I always wanted to use this little blown glass cloche for something!