First off, all the measurements are estimates. Potatoes never weigh out evenly, and the flour depends on the moisture content of the potatoes.
Steam the potatoes till done. Length of time will depend on the size of the potatoes. When done, peel the skins off. They will come off easily.
Flour your work surface well.
Rice the potatoes onto the floured work surface.
Adding as much flour as is needed, work the potatoes into a dough. This is a feel type of thing. Too much flour will make the gnocchi tough, and not enough will cause them to fall apart when boiled. Knead the flour into the dough till it's smooth, but still somewhat sticky.
Roll the dough into a rope about the thickness of your thumb.
Cut off pieces that are about 1/2 inch long. You can roll them off the tines of a fork if you like to give them more sauce holding ability.
Cook in boiling well salted water. Gnocchi are done about 2 minutes after they rise to the surface. DO NOT bring water to rolling boil like in the picture, as it's easy to over cook them and they'll fall apart.
Cut off a portion of the dough.