It can be used to generate blasts of fire or to provide illumination in the form of a small flame.
"Obey the command! Fire God, Come Forth!"
In the English-dub of the Cardcaptor Sakura anime, the phrase is shortened to "Element: Fire!".
Tsubasa Reservoir Chronicles
Unlike his counterpart, Tsubasa Li doesn't use the paper with the sword, he simply uses two fingertips to summon the spell.