Repentance. ‘תשובה’. The Hebrew word literally means ‘Return’ to represent the aspect of leaving the bad way and returning to the righteous ways taught in the Torah. We can do Teshuva every day before going to sleep. It helps cleanse the soul from negative ‘attachments’ and support a new beginning in the following day.
The most basic and yet powerful repentance is saying
“חָטָאתִי עָוִיתִי פָּשַׁעְתִּי”
“chata’ti aviti pasha’tti”
Loosely translates to “I have sinned, I did wrongs, I did crimes”. By admitting the wrongs, a person opens a path for correction and soul cleansing.
Even if a person did a lot of sins and wrongs, but say these words with intention before he dies, he will have a share in the world to come, after he goes through the cleansing process in Gehennam.