We all make mistakes and we are all in dire need forgiveness for the sins which we commit knowingly and unknowingly every day. It is only out of the mercy of Allah The Almighty upon us that He has facilitated many ways to attain forgiveness. As long as a person is a believer and does not practice any form of Shirk (associating partners with Allah The Almighty in worship), he can surely hope to receive forgiveness as Allah The Almighty Says (what means): {Verily! Allah forgives not (the sin of) setting up partners (in worship) with Him, but He forgives whom He wills, sins other than that, and whoever sets up partners in worship with Allah, has indeed strayed far away.} [Quran 4:116]
Ibn Taymiyyah said that a believer may ward off the punishment of his sins by one of the following ten ways:
- Repenting sincerely so that Allah The Almighty would forgive him, because the one who sincerely repents from a sin is exactly like he who never committed it.
- Asking forgiveness from Allah The Almighty so that Allah The Almighty would forgive him.
Performing virtuous deeds which expiate sins, Allah The Almighty Says (what means): {And perform Salaat, at the two ends of the day and in some hours of the night [i.e. the five compulsory Salaat]. Verily, the good deeds remove the evil deeds (i.e. small sins). That is a reminder (an advice) for the mindful (those who accept advice).} [Quran 11:114]
- Other Muslims supplicating for his forgiveness.
- Other Muslims offering the reward of a righteous deed they perform to him.
- The Prophet interceding for him with Allah The Almighty not to punish him.
- Allah The Almighty putting him through trials in this life, whether in his wealth, health, children or family.
- Allah The Almighty putting him through trials in the grave. 
- Allah The Almighty putting him through trials and horror on the Day of Resurrection.
- Allah The Almighty forgiving him out of His mercy.
Allah The Almighty says in a Qudsi Hadeeth (sacred narration): “They are but your deeds, I record them, then I pay you back accordingly; so whoever finds good, let him thank Allah, and whoever finds otherwise, let him blame no one but himself.” [Muslim]
Just as Allah The Almighty has granted us the means to attain His forgiveness and pleasure, He also gave us ways to avoid the Hellfire.
Allah The Almighty Says (what means): {Everyone shall taste death. And only on the Day of Resurrection shall you be paid your wages in full. And whoever is removed away from the Fire and admitted to Paradise, he indeed is successful. The life of this world is only the enjoyment of deception (a deceiving thing).} [Quran 3:185]
These are some of the ways mentioned in the Quran and Ahaadeeth (Prophetic narrations):
- Persevering through the death of three children:
The Prophet said: “Allah made the Hellfire prohibited for the one who buries three of his children (while persevering through it).” [At-Tabaraani]
- Raising three daughters, or sisters with a sound upbringing, and being kind to them:
‘Aa’ishah narrated that the Prophet said: “No one from my nation properly raises three daughters or sisters and is kind to them, but they will be like a shield for him from the Hellfire.” [Bayhaqi]
- Defending a believer in his absence:
Asmaa’ narrated that the Prophet said: “He who defends his brother in his absence against people who are backbiting him, Allah will free him from the Hellfire.” [Ahmad]
- Praying forty days with the congregation and attending the Takbeer al-Ihram (initial 'Allahu Akbar'):
Anas narrated that the Prophet said: “He who prays forty days attending the initial 'Allahu Akbar', will be freed from hypocrisy and from the Hellfire.” [At-Tirmithi]
- Possessing good manners:
Abu Hurayrah narrated that the Prophet said: “Allah will forbid the Hellfire to (even) touch the one who is gentle and lenient.” [Al-Haakim]
- Praying Fajr and ‘Asr:
‘Umaarah ibn Ruwaybah narrated that the Prophet said: “The one who prays Fajr and ‘Asr will never enter into the Hellfire.” [Muslim]