Whatever works for your kids–RGT, Love and Logic, spanking, time-out, etc.–CONSISTENCY is your friend and most important of all. If you’re going to tomato stake, do it consistently. If you’re putting them in time-out for throwing a tantrum, do it consistently. Kids are smart, and they know they’ll win if they can catch you at a weak moment. If you’re consistent and never let your guard down and always follow through, you’ll outlast them in the long run and they will start developing the good habits you want them to develop.
I see so many parents who have great intentions and ideas for improving their children’s behaviors, and they implement them…for a week. Then mom and dad get tired or distracted, and it’s all over. If you can really commit to staying one step ahead and always having a plan/natural consequence in place when bad behavior strikes, you’ll beat them at their own game.