Re: How do you...
I've been having the same problem as well except my mother doesn't work so shes always home and she stays up unusually late. I try to stay up past her bed time but if not then I do it really quite in my room with my door locked. If she knocks to check up on me I simply say I'm too lazy to get up or I'm on the phone, or doing homework, or something that makes me sound preoccupied.
It would be a good idea to do it in the afternoon with the door locked. If some knocks on the door you can always pretend to be half asleep and say your taking a nap. If your still in school like me, be sure to mention you had a long tiring day at school when you get home. That one works really well.