So many people complain that it's too expensive to go to the Snow Festival, but I don't think it's too bad.
AirDo is a Hokkaido airline that flies between various Hokkaido locations and the rest of Japan. Their flights are pretty cheap if you book a bit in advance. If you book more then ten days in advance and have a little flexibility, I think you could get a round trip ticket for around 20,000 yen.
Plus, their mascot is super cute.
Plus they have cute flight attendants.
Plus their name rhymes with hairdo.
Another thing is that I like to stay in cheap business hotels. I've stayed at Norte a few times; a single room runs around 4,000 yen. My friends are staying at capsule hotel Avinel (male only, 2,900 yen), and my brother stayed at capsule hotel Safro (3,800 yen). Both the capsules have spas and other interesting amenities, and Safro allows women, which is rare for capsule hotels. I'd like to try that next time.
And Sapporo is a really pretty city with lots to do and extremely awesome people. More on this later.