רַחוּם וְחַנּוּן חָטָאתִי לְפָנֶיךָ ה׳ אֱלֹקַי מָלֵא רַחֲמִים רַחֵם עָלַי וְקַבֵּל תַּחֲנוּנָי
Rachum v'chanun, chatati l'fanecha Adonai Elokai, malei rachamim racheim alai v'kabeil tachanunai
Compassionate and gracious One, I have sinned before You, Lord my God. Full of mercy, have mercy on me and accept my supplications
We rest our head on our left arm (or right if not wearing tefillin) during the first part — a posture of vulnerability.