Hello Chandan,
Just to be sure, I purchased the PTE practice tests and sample questions (Gold package I think). That was the only preparation I had. Although I am not a native speaker, my work requires me to interact with global clients regularly, so understanding various accents (listening) and speaking is not a problem.
Writing essay: Divide the essay into 4 paragraphs of 2-3 sentences each: 1. Introduction 2. Your opinion 3. Fact-based statements to back up your position or personal experiences 4. Conclusion. Use of decent vocabulary and punctuations is key. All they want is to ensure you can frame proper English sentences and communicate your point across.
Speaking: Just speak the way you usually do. Not too loud, no fake accents. Of course, no 3-second gaps!
Listening: Listen VERY carefully, probably close your eyes and listen if need be (and if you're not taking notes). I was having issues concentrating with so much noise around (outside noise).
Reading: No real tips here :\ Just try to understand the passages and not try to match the options word for word.
All the best!