Learning how not to yell

Ask my kids or my neighbors and they will tell you that I'm a yell-er.  Not at my husband but at my kids.  Most of the time they just don't listen when I tell them to do something nicely.  My voice just gets louder and louder until it hurts.  My mom let me borrow a book called Discipline: 101 Alternatives to Nagging, Yelling, and Spanking.  It's a really good book and I'm learning from it.  It's helping me to think like kids, they think they're being good but in our eyes it's horrible. 

I've been taking it slowly so I could use and understand each one before I move on.  This morning I just read about positive momentum and negative momentum.  If you start asking them questions with "yes" answers then ask them to do something you need them to do they are more likely to say "yes" and have motivation to do it.  That's what salespeople do and I never thought about doing it with kids.