Take this medicine and then take another (later)
Ou dwe bwe yon konprime e pran yon lot ankò
Take two of this medicine per day
Ou dwe pran du konprime pa jou
To be more specific, you could signify when to take it. This is often best to clarify and keep people from taking too much.
Take one in the morning and another when it gets dark. Only take two each day.
Pran yon nan maten e pran lot le li fe nwa. Sel bwe du pa jou.