How should I take Lorazepam?

A very close friend gave me 100 0.5MG tabs of Lorazepam. She said her doctor prescribed it for her to sleep, not for anxiety per say. So she was taking two in the morning and two at night. I want to take it for anxiety! How should I go about taking it? Any suggestions? I was told not to exceed 5 tabs per day, but I'm not sure. I'm aware of the with drawl. I am low on cash and have no health insurance.