Start by getting rid of pieces of food on the highchair. Do not forget to check all of the crevices of the highchair. Food stuck in cracks is a breeding ground for bacteria and germs, and the last thing you want is your baby getting sick because of it.
Next, remove the tray from the highchair so you will be able to clean the arm rests and the seat properly.
If you are using a highchair cover, remove it from the high chair and follow manufacturers' care instructions. Most highchair cover types however, are easy to maintain. Clean them simply by popping into your washing machine. For high chair covers made of plastic, clean them using a mixture of bleach and water. Add a tablespoon of bleach to a gallon of water and put some into a spray bottle. Bleach and water mixture is the most commonly used disinfectant in most child care environments because it is more effective in killing bacteria that soap and water. Spray the highchair cover evenly with your bleach and water solution and leave it on for two minutes. Wipe off the dirt using paper towels. If your highchair cover is very dirty, soak it in the bleach water solution for a couple of minutes and then rinse it thoroughly.
To clean the highchair's seat and arm rests, use a baby-safe all-purpose cleaner or highchair cleaner. Wipe the cleaner off using paper towels. Simply repeat this step until you have covered all the sections of the highchair's seat and arm rests.
To clean the tray, spray it with your baby-safe all-purpose or high-chair cleaner and then use paper towels to wipe it clean. Flip the tray over to clean the underside of the tray since it highly likely that your child got some food there as well. Spray it with cleaner and wipe it clean with paper towels.
To disinfect the entire highchair, spray all plastic surfaces with your bleach and water solution and use paper towels to spread the disinfectant evenly. Let your disinfectant dry completely.
Once a week, give your baby's highchair a thorough cleaning. Take it into the shower and scrub it using a clean rag and antibacterial cleaner. Using an old toothbrush, brush all of the dirt and grime off the highchair, paying close attention to cracks and small spaces.