To keep regular, drink plenty of water. If a person is chronically dehydrated, things won't move quite right.
Also, for many people, the mucous formed to digest dairy can cause a slowdown, and when you finally do go, it can be impacted a bit because the mucous has "glued" separate stools together. I would recommend cutting back on it or removing it from your diet altogether if you can.
I cut out dairy completely, and it's been nothing but smooth sailing for a few years now. I never need harsh stimulants and laxatives because my system will self-correct within 24 hours and even compensate for the "sessions" I've missed. In fact, I even like pooping. It's the only time during the day where I have exactly 45 seconds to stop, sit down and reflect about life, it's very refreshing. Sometimes, it even feels better to go twice a day if you need to, but being busy all the time, it's hard to think about doing the #2 if you don't daily urges. Maybe, you could schedule "I'm gonna go drop some at 9 AM" in your daily planner. The human body does naturally adapt very well to a consistent schedule.