The prophet (saw) said to Abbas there are ten things you will do that will wipe away your past, present, hidden, open, intentional, and non intentional sins which is the (salatul tasbeeh )

HOW TO PERFORM SALATUL TASBEEH
You will perform ablution with the intention to pray four (4) rakats. In each rakat you will read Suratul fatiha and any other surah from the Holy Qur'an. After that other surah and before you go for rukuu, you will recite:

SUBAHANALLAHI, WALHAMDULLAHI, WALLA ILLAHA ILLALAHU ALLAHU AKBAR (15) times, While in rukuu you'll recite it (10) times. After rukuu but before sujjada you'll rise up and recite it (10) times. In sujjada you will recite it (10) times. After you rise from sujjada you'll sit down and recite it (10) times before you go back to the second sujjada. In the second sujjada you'll recite it (10) times. After the second sujjad you'll sit down and recite it (10) times before you stand up for the next rakat. Before you realize it, all in all, you have performed seventy five (75) tasbihi in every rakat. That is how you will repeat it in the remaining three (3) rakats. It will now make the total number of tesbeeh you have recited to be 300, in the four (4) rakats. You will then recite the Tashahhud followed by Taslim i.e Attayi-atu lillahi, Azaakiyatu lillahi, Attayi batu salawatu lillahi, Asalmu alaika, ayyu anabiyyu, waramotu lahi, Wabaraka tuhu, Asalamu alaena, wa alaehi baadi lahi, solihin. You will then say: As-salam Alaekun waramotu lahi. (Twice) The first to the right side and the second to the left side. That ends the Sallatul tasbihi prayer.

WHEN TO PERFORM SALATUL TASBEEH Then he further said that you should at least try by all means to carry out this salat every day and if you are not opportuned then every Friday, if you are not opportuned then every month, if you are not opportuned then every year, if you are still not opportuned then once in your life time.

BENEFITS OF SALATUL TASBEEH
If you surely do it the way it is expected, then if your sins are aSalam.