How to fight the negative thoughts?

When a thought hits you or when you feel that satan is pressuring you into sinning — turn to Allah. Because He blesses protection to only those people who turn towards Him. Be mindful, if you do not turn to Allah you can not fight the evil both inside your heart and outside.

Stick to the remembrance of Allah. And do not be from people who forgets the purpose of their life on earth. This is a temporary shelter for the wrong doer. And this is a garden of happiness for people who can see beyond the issues, problems and troubles.