Shaykh Yasir Qadhi elaborates on the dangers of idle talk and how to protect one's tongue as referenced in verse 63 of Surah Al-Furqan.
The importance of guiding the tongue against vain talk is illustrated in the fact that it is a sign of believers. The Prophet ﷺ warned against the dangers of vain talk. When the tongue is involved in sin, it demonstrates the filth of the heart.
Things to avoid with your tongue:
We should leave anything that is not our business - gossiping
To mention something negative about a person in his absence - backbiting
Slander
Lying
Vulgarities and curse words