Cultivate a positive environment by reading and listening to more positive information and entertainment sources, and choosing to spend time around positive people.
How to stay positive: 11 Smart habits - Positivity Blog
Who you choose to spend your time with and the input you get from further away like the TV, the internet and magazines will have a huge effect on your outlook. To be able to stay positive it is essential to have influences in your life that support you and lift you up instead of dragging you down. So carefully consider what you let into your mind.