Wear gloves and open all doors and windows
Remove any solid vomit immediately
Blot wet areas with paper towels or clean cloths
Sprinkle baking soda over the affected area
Let the baking soda sit for several hours
Vacuum up the baking soda thoroughly
Clean the area with an upholstery cleaner or carpet cleaner
Use an enzyme cleaner on fabric, carpet, and mats
Wipe hard surfaces with warm soapy water
Clean seat belts with mild soap and water
Remove floor mats and wash them separately
Clean the trunk and under-seat areas
Replace the cabin air filter if the smell lingers
Place activated charcoal or odor absorbers in the car
Leave the car ventilated for as long as possible
Repeat cleaning if any odor remains
Have the car professionally detailed if needed