Fill four 8-oz. canning jars with milk up to ½-inch below the rim.
Pour 2 cups of water into the Instant Pot inner pot and place steam rack/trivet in inner pot.
Carefully place jars on the trivet and close the Instant Pot. You can choose to cover the jars loosely (with aluminum foil or jar lids without screwing them on).
Set Instant Pot to Steamfor 1 minute. If you don't have the Steam function, use the Pressure Cook function (High Pressure).
Do a Quick Release to de-pressurize the Instant Pot.
Open the Instant Pot and remove jars when cool enough to handle. Using a digital thermometer to measure the milk's temperature, let milk cool to 110 degrees F.
Remove skin (if present) from the top of the milk.
Add ½ teaspoon of starter yogurt to each jar and stir well.
Place jars back on trivet.
Place lids over jars ( but don't screw in the covers.) This will prevent condensation from dripping into the jars. You can also use aluminum foil.
Close the Instant Pot lid and set to Yogurt mode for 8 hours.
Press Cancel and open the Instant Pot and move the jars to the fridge for a few hours to chill.
Notes
It's best (but not absolutely necessary) to take your starter out of fridge and bring it to room temperature.
I used the full fat variety of Fage brand of yogurt.
I have not found a need to sanitize the pot before making yogurt. If you wish to do so, just run a water test like you did the first time you used your Instant Pot.
It is important to use canning jars or an oven safe dish.
Remember to save a few teaspoons of your plain yogurt for the next batch.