You will continue to remain happy when your each action is such that it doesn't cause sorrow to anyone.
In all that you do throughout the day check if any of your actions is such that there is suffering for anyone.
Also check if you are yourself happy with what you are doing.
Where the action is right, you will not experience unhappiness.
Take a thought in the morning that you will do what is the best throughout the day.
Also before you take any decision about any action ask yourself if it is going to harm anyone.
Your decision to perform the action or not should be based on this.
Be free from desire and you'll be free from anger too.
When the ideas that you have offered are being rejected, check what kind of feelings you are having.
Is there any irritation or anger? Where there is either of these it indicates that there is a desire for what you have said to be fulfilled.
When you are giving your ideas, just tell yourself that your idea is just for the good of all, if it is accepted by all it's good.
Even if it isn't it is nothing to get upset about. When there is no consciousness of 'it has to happen', you'll find yourself free from anger.