Remember that being thirsty is a sign of dehydration so hydrating means not waiting for the sign but preventing it through liquid intake. Think of your intestines like a water slide at an amusement park. You need water to move the cars down the slide. That's why hydration is such a big part of proper bowel movements. So, just keep working on that.
Beyond that, how is your diet? Do you eat a lot of fresh fruit? Do you get plenty of fiber? I have a son with a slow moving digestive tract. Always has been. We combat it with a strategy of a daily probiotic. He drinks a probiotic smoothie (Dannon activa brand bought in the dairy department of the grocery) or they also make a pill form. The second part of the strategy is a cup of purple grape juice a day. That was recommended to us by an ER doc when we were there evaluating if he had appendicitis when he actually had a bowel blockage of his own poop. Lovely. But he does go all the time too so it is confusing. Anyway, doing those two things as well as a generally heathy diet and exercise, keeps things fairly regular.
What are you sick with?