Step 3: Build and Support
Now the fun starts... Keep forming blocks and keep stacking. Keep adjusting front to back and keep stepping back to make sure both sides are arching in with the same degree and curve. As the pillars grow in, they will need support. You want to keep this as simple but as strong as possible. We used sawhorses with a simple board for the first layer. We supplemented smaller supports by using blocks of snow that didn't make the cut for the arch. Make sure you support the natural arch of the snow, do not over support it by pushing the curve up.