The exact time of August’s New Moon is 11:09 p.m. EDST. However, due to the action of the void of course Moon, your best bet is to avoid wishing on Tuesday, August 10, 3:10 p.m. – 7:00 p.m. & Wednesday, August 11, 8:04 p.m. – 12 midnight.
Therefore in AUGUST, your most potent times for wishing are:
Monday, August 9: 11:09 p.m. – 12 Midnight
Tuesday, August 10: 12:00 a.m. – 3:09 p.m. & 7:01 p.m. – 12 Midnight
Wednesday, August 11: 12:00 a.m. – 8:03 p.m.
*All these times are in Eastern Daylight Savings Time.