Hi Ashok,
First, you have to issue a show-cause notice asking for a reply to the allegations of misconduct. The notice may contain the date, time, place, persons involved, and other details of the misconduct. If there is no reply or an unsatisfactory reply, a warning is one of the possible punishments. The warning letter may be something like the one below:
The management has received your reply to the show-cause notice dated ----. The response is vague, unsatisfactory, and not acceptable. Considering the gravity of the misconduct, severe disciplinary action was warranted. However, to provide you with an opportunity for improvement, the management has taken a lenient view.
You are hereby issued a strict warning to improve your conduct. If no improvement is found and you commit misconduct again, the management shall be constrained to take strict disciplinary action against you.