Play as Raven:
1) From the main menu go to the "Options" menu
2) Select "Cheats"
3) Enter: RidinwRaven (you should hear a sound confirming the entry)
You can play as Raven; just select her from the list of boarders before you begin

Disable Tree Collisions
At the Cheat Menu, enter 'buzzsaW'.

Free Movement
At the Cheat Menu, enter 'ZiPster'

Level Select
At the Cheat Menu, enter 'GimmeGimme'.

Perfect Jumps
At the Cheat Menu, enter 'StickiT'.

Low Gravity
At the Cheat Menu, enter 'MegaLeg'.

Steezy Snowboard
At the Cheat Menu, enter 'ChillinwSteezy'.