How should a Muslim get rid of bad thoughts?

When you fill your mind with materialism; bad thoughts will start settling in it. A mind or heart without God's remembrance is the right place for evil to land. I have experienced this myself when I was in Dubai. I was so astonished at what was I thinking. I, then, realized that it was due to the laziness that I had showed towards Namaz and Quran. We become soulless from the point (when) we abandon God's obediency. That's why it can be seen that the people who stay liberal (run away from religion), easily fall for vice. A practicing Muslim is therefore stronger in aspects of faith, discipline and character than others. Allah has created signs for us in this world to follow. We can now choose to pay heed towards the right, or stay ignorant till we finally meet our fate.