If I give you something called a 'formula', then it would only be through my eyes, it would only be through my experiences. Even you and me are different and so are different our styles of looking at children and handling them. So, it would be pretty difficult to say what exactly to do and what not to do. Still as you say there are some factors which are important for all the couples - dating couples of course, irrespective of where they live or from what background they come from.
For example, the trust unto each other. Trust is the most important binding factor that can keep a guy and a girl together for the whole of their lives. Secondly, as only trust would not help, so also there should be love for each other too. Understanding shown towards each other can do wonders. Caring is also a key factor. How much you care for your partner you have to show that through words and actions. If these small factors are taken into consideration, they I think, you have found the formula for a successful relationship. What I tried to tell you are all the positives. If you think they are worth it, then just spread the word.
