How to protect yourself from the punishment of the grave and Hell fire

Shaykh ibnu Uthaymeen said:

A muslim shields himself from them by performing righteous actions which brings him closer to Allah. A righteous action comprises of two conditions:

1st: Ikhlaas (sincerity) for Allah, by way that he does not intend his actions of worship except for Allah and the Hereafter. He should not intend showing off to other people in order to earn praise or something from the Dunya.

2nd: That he does not introduce a new affair (innovation) from himself in Allah’s religion, for indeed Allah does not accept an action except if it’s done sincerely for him and is in agreement with his legislation.

Allah says in a Hadith Qudsee: “I am free from having a partner (equal) whosoever performs an action and ascribes a partner with me in it, i will abandon him and his shirk” [Muslim: #2985]

And the Prophet (sallaaAllahu alayhi wa sallam) said: “Whoever performs an action that is not from our affair (religion), then it is rejected” [Al-Bukharee # 2550 & Muslim #1718]

And from the means to protection from the punishment of the grave is that he protects himself from urine and cleans it completely. As the Hadith of ibnu Abbaas mentions that the Prophet (sallaaAllahu alayhi wa sallam) passed by two graves and He said: “Indeed they are being punished, and they are not being punished for something that was difficult, as for one of them he never used to protect himself from his urine and as for the other he used to walk around tale-carrying” [Al-Bukharee #215 & Muslim #292]

And from the means also is for a person to constantly seek refuge in Allah from the punishment of the grave, for this reason the Prophet (sallaaAllahu alayhi wa sallam) commanded us to seek refuge from four things in the last tashahud of the salaah: “O Allah truly i seek refuge in you from the punishment of the grave, from the punishment of the Hell fire, from the trials of life and death and from the evil trial of the dajjaal” [Al-Bukharee #798 & Muslim #587]
Fataawaa Noor Alaa Ad-Darb (12/12-13)