What prevents us from experiencing peace? How can we be peaceful?

Our agitations prevent from a peaceful state. Peaceful state is natural and is ever remaining, our agitations created by us only. We can be peaceful permanently if we work on removing agitations and there are four causes of agitation:-

1. Ego – Ahankara - Identification with actions and doing them gives rise to the notion of doership or ego. ‘I speak, I think’, which in turn creates agitations like ‘I am unhappy, I am restless’ and so on and the like.   
2. My-ness – Mamata – The ego arises in the body and myness is the notion in the things related to the body, my house, my mobile etc. It creates agitations like jealousy, possessiveness, fear of loss and etc.
3. Desire – Kamana – Wanting on an object or being thinking it will give me joy is desire. It creates agitations like restlessness, emptiness etc.
4. Craving – Sprah – It is the longing for the object already enjoyed. It creates agitation like continuous want, re-living past memories, imagining and anticipating future pleasure. 

Peace underlies all agitations. Self-knowledge destroys the false ego. Once the ego is removed, my-ness, desires, and cravings totally disappear.