You can probably milk her twice a day at this stage. As to when, that is up to you and what suits you. I wouldn't leave her more than 14 hours between milking though. When I was on twice daily milking, it would be around 9.30am and 7.30pm but I have done 9am and 11pm. If she's only producing a small amount, ie less than a couple of litres a day, you only need to milk once a day but the yield will stay up better if you milk twice.
Continue milking until she is stripped out. When the milk stops flowing, I always massage the udder as they seems to hang on to some. I then take a bit more, massage again and take more. I do this until there isn't any more to take. It doesn't take very long. If you don't strip her out, she is at risk of mastitis.