Controlling an emotion while gambling depends on the person. Others will find it very difficult while others can easily cope up with it. The factor that greatly affects this thing is how well a person disciplines himself and how he sees things in gambling. How well he goes along with his initial plan and how well he accepts the results. Planning ahead also helps. As for the gambling result, it is all random so there is no fixed strategy in order to win. One should be fluid while not losing their self-discipline and always be ready to have a break whenever your initial plan isn't going well.
It is very clear to know that human being consist of different people including the mindset, discipline, knowledge and ways of controlling emotion. Even though I find it difficult to do it, it is still possible for others to find it easy and it is the right thing. I know, discipline in gambling is very necessary while we must continue to solidify the original plan. Even though it is difficult, because of that there is also an opportunity to win something in gambling. Discipline and planning are the right keyword.