Keep an eye on the NBC website to learn they are holding auditions for "Last Comic Standing." Every season they have open calls in four or five major cities.
Go to the open call in one of the major cities. Show up with plenty of time to spare. In the past, production assistants have handed out a limited amount of numbers that permit entry to audition in front of the judges. Many comics camp out overnight in order to get their number.
Speed up the process by having required forms filled out before auditions. These forms are available on the "Last Comic Standing" page of the NBC website.
Keep material appropriate for the show. While comics are not usually G-rated, jokes for this audition will need to be relatively tame, and appropriate for network television. The judges will be instantly turned off by raunchy, racy material.
Avoid over-used subjects that will bore judges and audiences. These include subjects like dating, race and ethnicity.
Submit a video showcasing material to NBC through their website. If not able to make it to open casting, make audiences laugh online with a video of original material.