I just started using a new skin care regimen for acne, i want to only wash once per day. Morning or Night?

Is it best to wash in the morning or at night? or for say i workout and need to take a shower, do i just wash without using the facewash and just moisturize? i don't know whether i need to wash in the morning or at night. i mean i'd like to be clean before i go to school so i figure morning, but then i don't want to go to sleep and breakout from not washing......need istance (again i only want to use the regimen once per day and i don't really want to mix products!)