How to overcome negative thoughts?
I used a very interesting method of Jay Shetty who is a writer of very famous book "Think like a monk".
In that book he mentioned a method of Spot, Stop and Swap.
To purify our negative thoughts we have to aware of that negative feeling or that thought that is we have to spot it.
Then we pause to address what the feeling or thought is and where it comes from that means we stop to consider it. And the last, we have to amend our thought or feeling with positivity that means we swap it. So its a very easy and useful method of being a person with full of positivity.