How to maintenance equanimity in the daily life? I would like to understand in the short and simple how to deal in the daily life.

When I have the emotion and I feel the sensation i.e. cold in my palm, what should I do next?
I aware that this feeling cold will be gone sometime later. But how do I know that I do not react to that sensation blindly? 

Looking forward to see your answers.

With a lot of metta,
PP
If, during your formal practice, you are able to purify the mind of the hindrances then you can apply that level of concentration and purity of mind to experiences outside of formal meditation.

Purity of mind means that you are able to attend to a sensation without adding stories to it that are rooted in the hindrances to mindfulness (attachment, aversion, doubt, worry and slackness/laziness/lethargy of body and mind).

For example:

If you have warm hands and you say, "I like warm hands; they are so pleasurable!" That is attachment . . .

If you observe cold hands and you say/think something like, "I hate cold hands." That is the hindrance of aversion . . .

If your hands are cold and you ignore mindfulness because you do not believe it is beneficial then you have doubt about the practice . . .

If you have cold hands and you say something like, "I am scared, what will happen if my hands get too cold, I could get hurt and experience painfulness." That is worry . . .

If the mind becomes sluggish and ignores the sensation because of that sluggishness then you have lethargy of mind. 

Instead of saying or thinking any of these things you should simply observe the sensation in the hands. If you can not do this it is a sign that there is still work to be done in regards to purifying your mind. If those thoughts arise notice them, then let them go and try to return to observing the bare sensation.