1) Imagine the spell to be cast

2) Determine the Sphere(s) and ranks required

3) Determine the DC necessary (add any modifiers to spellcraft DC - quicken, bigger radius, etc, spend any quintessesnce to reduce DC)

4) Make a Spellcraft Roll

5) If successful, consult the basic rank effects to determine outcome

6) Modify for raises. (a raise is every full +5 the spellcraft roll exceeds the necessary DC to cast