The recommended portion of pasta per person is 2-3oz (60-85 grams).
Salt the water to cook the pasta just like sea water.
You might not need to use all of the reserved pasta water, see how much you need to make the sauce as you make it.
Fridge: Store in the fridge in a sealed container for up to 3 days.
Reheat: Reheat the pasta in a skillet over low-medium heat, and add a splash of water to thin out the sauce. Do the same if using the microwave.
Freezer: I don’t recommend freezing this pasta, as I found that it breaks when frozen and reheated.