"Faking your own death takes a lot of planning, care and closemouthedness.
First, you need to figure out what kind of death you want to have. For example, suicide, accident, or murder.
Next, you need to figure out how you will fake your own death.
Suicide and Murder are the two easiest to fake, unless you live in a town with an excellent police department, or have a suspicious parent/guardian/spouse who loves/hates you a whole lot and has lots of money to spend.
Accident is more difficult because you need to lead people to the conclusion that you are dead without actually producing a body. (unless you mean to kill someone?!)
Suicide can be faked most easily; for example by leaving a suicide note, and jumping off a bridge and not resurfacing while making sure there are plenty of people to see you and not actually managing to drown yourself. Research is crucial! Make sure you know how to swim well and how to land in water from a high altitude without hurting yourself.
Logistically, you need to have a getaway car secreted in some nearby spot and don't be stupid and pack up your room. Dead people don't need their clothes and cds.
Murder is also fairly easy, but this often requires pinning it on someone else, which may cause moral issues and also requires that the patsy have a plausible motive. Being murdered by an anonymous person, like a mugger or a thief, is very unlikely to work since your death is not easily verifiable and they can't have a plausible motive to work with. Think Double Jeopardy, and Wild Things. Again, the key is not leaving a body, but still making it obvious that you are dead. Smears of blood, teeth and body parts such as fingers are often sufficient identifiers, but use your imagination.
Accident is the hardest to fake successfully without having a body, so the only real way to do it is by the 'missing and presumed dead' method. A climb of a dangerous high mountain, or hiking alone in the forest, or driving somewhere and never making it to your supposed destination and leaving a burnt out car and smears of blood all over the place should work, but again, use your creativity.
Faking your own death is the easy part. The tough bit is emerging from your charade as a new person. If you're in the US you need a new Social Security Number. You need a birth certificate to receive a SSN. Where do you get a birth certificate? Those sort of records are notoriously hard to find. You're not likely to get one just by asking. You can't use just anyone's either. If you use one from someone who's still alive, or worse already dead, you're back to zero and probably incarcerated for Identity Theft.
A popular "film method" is to get a birth certificate for an infant who died shortly after birth because, supposedly, Death Certificates aren't issued for infant deaths, or some such nonsense.
Unfortunately we all know that the movies aren't real life. It's easy enough to get a fake ID and live under an assumed name for a short period on time, but the first time you get pulled over for a minor traffic infraction, it's The Big House for you."