Water in take

I'm so bad about drinking water. Unless I'm like dying of thirst I won't drink more than a few sips. My skin is awful and I have a few stubborn pounds that won't go away and I've been told by my body builder brother in law that a lot of it is probably due to me not drinking enough water. So my question is this. How much water should I be drinking a day? (I'm 5'9" 150 pounds. I know people say 8 glasses but how many ounces? I have a 24 ounce  water bottle and I can't imagine trying to drink 8 of these a day!) and how do you keep yourself on top of how much you drink? Anyone else have an issue with drinking water? How do you deal?