Begin by scraping any excess vomit from the fabric. Run fabric, inside out, under cold water to flush out as much vomit as possible. Pretreat with prewash stain remover, and launder in the hottest water the fabric will allow.
Pre-treat stain with detergent or spot treatment and soak in warm water. You can sprinkle un-seasoned meat tenderizer onto stubborn stains for extra removal power.
Run fabric, inside out, under cold water to flush out as much of the formula as possible. You can use baking soda to neutralize the acid from baby’s spit up as well, preventing yellowing stains.