Bring a medium pot of water to a boil, add salt.
Add noodles and allow water to return to a boil.
Set a timer for 7 minutes.
Take out one noodle and bite it.
If the noodle is still hard in the middle, or you see a white "dot" in the middle of it, then it isn't done and you need to cook it a few more minutes then check again. Most pasta cooks in 7-10 minutes.
When the pasta is tender, drain the water off. A calender is ideal, but if you don't have one you can cover the pot with it's lid slightly askew and drain the water into the sink that way.
Usually one 20 oz jar of spagetti sauce is perfect for 1 lb (4-6 adult servings) of pasta. But if the "packet" came with the noodles, they are probably the right ratio.
You can toss the hot pasta in the sauce, or you can heat the sauce separatly and pour it on top.
Parmesean cheese would be a nice addition.