Your one-time electronic contribution will be debited on the date you specify on the donation form. Recurring monthly donations are deducted on the 16th of the month. Twice-a-month donations are deducted on the 15th and 30th of each month.
Since your contribution is made at a pre-set time, simply record it in your check register on the appropriate date. Electronic contributions will appear on your bank statement as well as your online banking report.