Modified entry here http://www.newgrounds.com/art/view/stelamoris/elf-motivation-poster-fix
I realized a lined of text was not straight. Hope someone sees it.

Well
Firstly, I did a sketch of my idea. I wanted to do it traditional but I didn't GET the materials to do it in the style I wanted.
So I figured to do it digitally but make it look traditional. So I went through old books and collected blank paper that looked old and had texture. Scanned all of them and put them on separate layers each in medibang paint pro. Then adjusted the opacity of some while for others I did other adjustments. Basically I was trying to make that 'special paper' like the one in my mind.
After that, I drew the words 'santa, elves' and 'good boys and girls' on a paper I thought had nice texture with pencil and also the picture of the mug. Scanned these images and put them in their appropriate places on a overlay layer so it looks drawn on the paper due to the texture created by the pencil on the paper originally scanned.
Then I drew in lighter parts on a hard-light layer and darker parts on a darken layer.
I drew the snowflakes in medibang, two sets each on separate layers. One had white snowflakes then had the opacity lowered. While the ones to the edge had dark brown snowflakes with the opacity lowered. Then I went and gently erased parts of snowflakes making patches of different opacities.
I used my favorite brush so far in the whole wide world 'fade in-fade out'. Medibang is the only free software that I know that has that brush. I used it to add the fine details like the steam, the shine on the words( the rest of the words were medibang fonts unfortunately) and the santa's signature and stuff.

I think this covers how I did this. Hope you are satisfied and thakyou for the comment and merry christmas when it comes.

oooops
Just realized you only asked for the snowflakes effect. O well.

Thank you and merry Christmas to you when it comes.