How does a defendant appeal a criminal conviction?
Either a jury or a judge may find a defendant guilty and sentence him to a term of imprisonment. Both the determination of guilt and the length of the sentence can usually be challenged on appeal.
In order to appeal a conviction, the defendant has to file certain paperwork with the trial court notifying the court of his wish to appeal.
There are very short deadlines after a defendant is sentenced for the paperwork to be filed, so the defendant must act quickly. If the defendant does not file the proper paperwork before the deadline, he may forever forfeit his right to appeal the conviction.