Paint your bird houses whatever colors you'd like. We planned ours out so we had a variety of colors and they all coordinated.
If you want to add any colored glitter to the trim of your house, now is the time to do that. Glitter looks pretty on doors and window trim. Add a thin layer of glue over the painted trim and sprinkle coordinating glitter overtop.
Now, add snow. Paint a thin strip of white paint along the edges of the roof of each house. This makes the snow really "pop" on the edges, where in real life it would pile up the most! Let dry.
Mix together your various white and clear glitters and fake snow in a bowl or other dish.
Add a thin layer of glue over the entire roof, and under/around any windows or doors where you want some snow to "fall" and use your fingers to sprinkle your glitter mixture over top of it. Let dry. IF you'd like, you can add a coat of Mod Podge on top of your glitter once try to help keep it from shedding.
The final step is to add your accessories! You can also add some snow and glitter to these with a little bit of glue. Then hot glue them to the doors, windows or porch of the houses.