NEVER OVERCOOK PASTA...! The operative words here is Al Dente. which means firm to the tooth, chewy, slightly undercooked.
Use Lots of water:
I use about one gallon of water for each pound of pasta. This helps the pasta will keep its shape and keep the excess starch from sticking to the pasta, especially with FRESH pasta. Keep the water boiling the entire cooking time.
Add salt and oil to the water.
The Salt helps the water boil hotter and the oil keeps the pasta from sticking together.
Add all the pasta at once:
This prevents uneven hardness, stir the pasta when you put it in the water to loosen the strands. Stir it several times during the cooking process and again right before you strain it.
* Try cooking pasta in chicken, beef or lobster stock for added flavor.
Test fresh pasta for doneness after 5 minutes, and dry pasta for doneness after 8 minutes, cook longer if necessary. Pasta is done or Al Dente, when it is tender with a slight crunch in the center, thicker pastas will take longer to cook and tubular pastas will cook faster.
Add Pasta Directly to the Sauce:
When the pasta is done, strain it immediately into a large strainer or colander, and add it directly to the sauce, *you may also rinse some of the starch off the cooked pasta with hot water and then add it to the sauce.
If you are going to cook the pasta ahead and re-heat it when needed: Rinse it with lots of cold water to shock it and stop it from cooking. Drain well and coat the pasta with some vegetable oil and cover it with plastic wrap. I use vegetable oil to oil my cold pasta, I find that olive oil gives the pasta a funny taste.