There are three important things to remember when cooking pasta. First, undercook it slightly. You want it to be just al dente which is usually about 1 minute less than the box suggests. Second, save some pasta water before you drain the noodles. That starchy liquid will help bring your sauce and pasta together. Lastly, finish cooking your pasta in your sauce. The flavors will meld together and the pasta will absorb some of the sauce as it finishes cooking. For more details, read this article on How to Cook Perfect Pasta.