the noodles are ready. Just have your boiling water in a large pot ready to go. I don't start the noodles until we are done with the appetizer course. When we sit down for salad, I drop the noodles into the water. Depending on how long it takes to boil, the noodles can be ready by the time you are done with the salad. If not, no one really minds if they have to wait a few minutes for the main course.
I have never used any special technique to keep pasta warm, but I looked it up. I found the following technique on a couple of recipe sites. This sounds something like I used to see my mother doing. You can try it if you don't want to go with waiting for it to be ready while eating your salad course.