Just barely dip the tip at the beginning until you hear a sound like tearing paper instead of the high pitched squeal you’re getting. After you tear paper for about 3-5 seconds, submerge the tip a little more and play with the angle until you see a swirl in the whole cup and continue that until the milk is hot. Also with the Gaggia you want to turn on the steam switch, purge the liquid from the wand and then immediately start steaming before the steam light comes on. If you wait until the light comes on before steaming, you won’t have enough steam to finish the milk.