Try drinking 2 glasses of warm water in the morning when you first get up. Some people put freshly squeezed lemon juice in it, but I don't.
Here's my morning routine: Get up, heat up water, drink one glass immediately. Take a hot shower. Drink the other glass. Then exercise---I do Bikram (Hot) yoga. There is one exercise in there that helps constipation. You drink one glass of water, then (while lieing on your back) pull one leg towards your shoulder, then pull the other one, then pull both.
Also, you should make sure you are getting enough magnesium.