The moon gets a full hit of noonday sun so your exposure should follow the "sunny-16" rule. You don't need mirror lock-up, although a tripod certainly cannot hurt.

The sunny-16 rule says, your exposure is f/16 and your shutter speed = 1/ISO, so if your ISO is set to (for example) 400, you'd be shooting at 1/500th sec and f/16.

Focus, of course is infinity.