In a bowl, using either an electric handheld mixer or a whisk, start beating the coffee powder with sugar and water. It will be a bit grainy at first, but a frothy mixture will soon start to form. After beating for around 5 minutes, you should have a pale, frothy and thick consistency of the dalgona mixture.
In two separate glasses, add the ice cubes, if you want your coffee hot, add hot milk. Scoop up your dalgona mixture and place on top of the milk and you're done! Before drinking, mix your drink otherwise it'll be too bitter.