Character Sheet
Before starting play, you'll want a sheet of paper to keep track of your character. You'll want this info down - your name, class, and level; your max Hold, Hand, and Base; your initial Ability and Skill, with open spaces for more; Exp. to level up; Gold; a space for Inventory; your class's Shop.
When I've sustained half damage from an attack, I tend to flip that attack card upside-down, and I write the actual damage I've taken next to my Base. If monsters have received more or less damage than what my attack cards show, I find a blank spot on the page and jot down the monster's active Base and the damage it's taken.
I keep track of Gold and Item Bonuses in the top right-hand corner of my page.
Once you've got this sheet laid out, you shouldn't need any reference materials - at least, until you start learning skills and abilities.
Misc. Rules
Ethereal Imbalance - if, on the initial draw, two active Bases appear that would normally cancel each other out (i.e a <310 and a ^10), pick up these Bases, shuffle them back into the deck, and re-draw them.