There are three important steps that you must use in carpet stain removal, hopefully before it has a chance to set in your carpet:

Apply: Dampen a clean, white (not printed) paper towel with a cleaning solution. Then moisten the carpet with it. Avoid thoroughly wetting the carpet, as this can damage the carpet and backing.

Blot: Absorb the excess liquid from the carpet by pressing straight down with a clean, dry, white paper towel. Do not rub. Place a half-inch thick pad of clean, dry, white paper towels with a weight on top and leave overnight if necessary.

Scrape: Gently scratch the soiled area with the blunt edge of a spoon. Scrape from the outside edge of the spot toward the center.