I will assume for now that you have chosen a general shape on how you want to set your decoy spread. Once you have done this attraction and realism come into play. I will break each one down seperatly and why each is important.
You must attract the geese first before realism matters!
From a distance a snow goose flock and your decoys look like blobs of white. As the geese get closer the blobs turn into smaller blobs and the blue geese start to show up. As the birds get closer and lower they begin to see the details on individual snow geese. Details like heads on birds or decoys.
Maximize Attraction and Finish More Geese!
Snow goose hunters can maximize the attraction power of there spread by making it look as big as possible (so the geese can see it from as far away or high as possible) and packing the realism of your spread where it counts. I do this by setting a spread built for attraction at a distance and realism near the kill hole.
I start by having the outside of my spread be all white decoys. This makes my spread look bigger and able to be spotted from much farther away. As the decoys and birds get closer to my blind I want to increase the realism of my spread. I change my spread from being all about attraction and more about realism. I do this by increasing the percentage of blues in my spread and try to make it match the snow to blue ratio for the flyway I am hunting. I also increase the percentage of headed decoys on my Feathertek windsocks. See the diagram below for a visual:
Making you a better snow goose hunter,