How do I prepare for extempore to get into Delhi FMS?

One such way is to google a list of extempore themes, talk about each one, and record your performance. If you can communicate well, this is the ideal approach to practice.

• Brush up your current affairs and general awareness. 
• Practice as much as possible with friends, family, or in front of the mirror.
• Improve your vocabulary and grammar.
• Learn how to organize all of your points and ideas.
• Prepare subjects linked to current events, social and economic problems.
• Make an effort to communicate in less time.
• Improve your body language and vocal modulation.
• Try to converse in a lighthearted and welcoming tone.