The majority of the set for 'Elf' was 3 portals. 2 were soft goods and 1 was a hard scenery portal.
For these drops I used a garden sprayer with a fine mist to create the blue gradient and masking to create the snow drifts and snowflakes.
Below is a photo of the portals after installation.
The floor for 'Elf' was a spatter and drag done with a garden sprayer and a push broom. I used a similar masking technique as the drop to create snowflakes on the floor.