There will be many signs for the Day of Judgement as told by Allah in the Quran and Prophet Muhammad.
According to Sunnah, the Dajjal (the Deceiver), the Mahdi (the Guided One) and Prophet Jesus (Isa) will be on Earth the days preceding the Day of Judgement. The Dajjal will mislead people and the Mahdi will precede the coming of Jesus and will fight for Islam.
The event of the Last Day will begin by the blowing of Israfil's horn, and people will go through various stages before they meet the almighty Allah. There will be a gathering on a white, vast featureless ground, and be called on by Allah where the angels will recount the person's good and bad deeds. According to these, Allah will judge whether the person should go to Paradise or Hell to abide in forever in the afterlife.