Most Keri occurs as a result of impure thoughts that pass through the mind throughout the day. These strengthen the animalistic soul. When a person goes to sleep certain parts of his soul leave him. These parts of the soul are associated with the conscious mind, with their protection gone the impurity takes over. On a simple level, all of ones thoughts from the day roll through his mind as he sleeps and now he doesn't have the same level of will power.

When a person has previously sinned by being Pogem Habris, he causes demons to be created. These hang around him at night forcing him to have impure thoughts. One can do things to protect himself, however if his Lilim are powerful they will use the slightest opening to break through.

Here is a list of things one can do.

-Do not think impure thoughts or look at impure images during the day. If these thoughts enter your mind immediately push them away. This becomes easier as time goes on. There are certain verses and Divine names one can meditate on they make it a lot easier, learn the meditations from our other writings.

-Say Kriyat Shma before you go to sleep. It is best if you say the whole ARI version.
The more concentration that is placed into the words the better it will work. There is nothing that burns the klipot like the ARIs Shmah, it is also a mighty rectification for past sins.

-If you wake up in middle of the night try to wash your hands and say over at least the two verses of Shmah and Boruch Shem.

-Try not to go to sleep when you are angry or depressed there is nothing that gives Klipot power like depression. The opposite is also true the happier you are the less hold they have over you.

-Torah protects more then anything the more Torah you study during the day the less of a chance you have of seeing Keri. Try to study Torah right before you go to sleep.

-Always sleep on your side. Go to sleep on your left side, after Chatzot you may turn on your right side. Never ever lay flat on your stomach even when you do not want to sleep.

-Do not wear tight pajamas or underwear.

-Do not sleep with socks on; you feet should stick out from the blanket.

-Do not use a blanket that is too thick.

-Make sure there is no dirty laundry anywhere around your head.

-Get a Kipa that will not fall off when you sleep, try the white ones the Breslev people wear.

-Place a small rock under your pillow. Yackov who never saw Keri in his life always placed a rock under his head.

-Remove all metal objects from your body, such as keys.

-Do not eat anything that warms the body before going to sleep. This includes any meat, eggs milk and cheese.

-Get married according to Halacha and keep the laws of purity.

-Do not sleep alone in a house, if you have to then light a candle for a Tzadik and place it in your room, it might help you out.

-Place aside some money to give to Tzdakah the next day if you are saved from Keri.

-Make sure the Mizuzah on the door is kosher and written by a G-D fearing Sofer.

-Make sure that there are no impure objects or pictures laying around the room.

-When you go to sleep chant a verse over and over like a mantra. You will fall asleep with the verse in your mind. This will help you regain control of your mind when the demons start plying with you.

-If you know the meditations sometimes you can gain control of your thoughts while you are sleeping and use the names to kill off the Klipot.

-Sometimes you will be saved and you will wake up just in time this is due to some merit you have.

-If you wake up and feel the demons around you say "Impure ones, impure ones go away. Say this three times. Then get up and wash you hands. Say over the beginning of Shema and chant Yoshev Beseser.

-Hand out this paper to other people, the merit of saving others will protect you as well.

-If they do Keri you go to the Mikvah immediately. If you cant change your clothes and do one of the alternative methods brought in our writings (40 hand washes with shem 72AB or 9 Kabin). The next day make sure you say Tikun Klali. If you have to go back to sleep it is highly recommended you change beds.

-Rabbai Aharon Ratah brings down to learn18 pages of Talmud and 18 chapters of Mishnah the next day.

-Remember even if you try everything and you still see Keri, do not let this leed you to be Motze Zera Livatala. Actively being Pogem Habris is a much bigger flow.

-Rabbi Nachman of Breslev said not to worry to much about Keri, as you purify yourself it will stop. Just make sure to go to the Mikvah and say Tikun Klali the next day.