The Holy Mysteries - Confession. Unlike most protestant sects, we don’t really practice a general confession as part of our regular worship, wherein we all recite a confessional prayer and are then given a general absolution. Like the other Holy Mysteries, Confession in the Orthodox Church is at once both a private matter between the priest and the penitent, and a public matter as it’s conducted in front of everyone. We usually stand right in front of the icon of Christ on the Iconostasis, as it is to Him (not the priest) that you’re confessing. The admonition the priest will say to you sets it out pretty well:
“Behold, child - Christ stands invisibly before thee to hear thy confession. Be not ashamed, neither be afraid, and hide nothing from me, rather do not fear to tell me all that thou hast done so thou mayest receive forgiveness from Our Lord Jesus Christ. Behold, His icon is before us and I am but a witness, that I may bear witness to Him of all that thou dost tell me. If thou hide anything from me thou shall have the greater sin. Take heed therefore lest having to the physician thou depart unhealed.”
After your confession you receive the absolution from the priest, which again is fairly telling:
“May our Lord and God Jesus Christ, through grace and compassion of His love for mankind, forgive thee, my child of all thy transgressions, and I an unworthy priest, through His powers granted unto me, do forgive and absolve thee from all thy sins, in the Name of the Father, and of the Son, and of the Holy Spirit.
When we come up for confession, even our posture is penitential - we bow our heads before God as we will again later in the Divine Liturgy, and when we receive the absolution, we kneel (if able) and allow ourselves to be covered by the priest’s stole. The canons forbid the priest from ever sharing anything told to him under the confessional seal, and it would result in his defrocking if he were to; not to his wife (if married), not to the courts, not even to the bishop. As to the frequency expected, you should approach for confession at the very least monthly, and ideally, before each time approaching the Chalice for Holy Communion. If for some reason you can’t remember your specific sins or haven’t prepared as adequately as you might have hoped to, you can always confess, “for all those sins which I cannot now recall I am truly sorry.”