1. Persistence
Nothing in the world can take the place of persistence, stay there till the end. This is key element of any success story. Take this as digging for the gold, you may digged many feet, however none of them will count till you reach the gold and imagine you stopped digging at the very last foot when you were just one hammer away from the gold.

2. Overcoming the fear of failure
Fear to fail this is what actually fails many startups. Failures are lessons that every entrepreneur must know, as entrepreneurship is a business of calculative risk-taking.

3. Paint your thought
Ability to communicate your thought is a skill that entrepreneurs must develop. Remember your perception will never match with the person working with you. You must able to paint your thoughts on paper.

4. Do things that you do not like
While executing your idea you will do lots of things and they will constitute of things that you do not like. You have to come out of your comfort zone and doing things that scarces you is one way to expand your comfort zone.

Source: https://www.quora.com