You should not get into the details. As simple as…
I committed…
adultery X times.
sex outside of marriage X times.
masturbation or impurities with myself X times.
The only details that should be included are things which may change the gravity of sin.
sex with a minor, animal, person of the same sex, rape or incest, etc. or when another sin may be included such as, anger, vengeance, or jealousy. Perhaps your spouse was unfaithful and so you were unfaithful out of spite or vengeance. Things of that nature should be included.
Other than that, no gory details. You don’t want your confession to become an occasion of sin for the priest.
