Don’t add oil to the cooking water.
Adding oil to the cooking water to keep it from sticking will cause the sauce to slip off the pasta.
Salt like you mean it.
The cooking water should taste like ocean. This is the only time you are able to season the pasta and keep it from tasting bland.
Wait for a rapid boil.
Starches in the pasta absorb water instantly and so you want the water as hot as possible to begin cooking properly. Adding the pasta too soon may cause it to cook improperly.
Give it a cold shower.
Slightly wash the pasta with cold water after straining it to let it from sticking.
Stir during cooking.
Occasionally stirring the pasta while cooking will keep it from clumping together.