Avoid overheating/burning milk
It is also important not to overheat your milk. The milk will have the sweetest and most velvety texture between 140-150 F°. As you froth past this point the milk will lose its sweetness, the froth will take on a gummier texture, and eventually the milk will scald and begin to taste burnt. The video below explains how to use a frothing thermometer so that the milk is kept within the ideal range.
How To Use a Thermometer to Froth Milk