how to show possession

This will depend on how long you have been away from the house. This is not a question of whether somebody breaks in and stay there for 3 days and therefore they can claim possession. In this scenario you will still be the rightful owner. It is not an easy task to claim possession. I hope this helps.

Subsequent to the registration of your sale deed you should have obtained property tax receipts and EB bill, water and sewage connection.. Mutation of revenue records in your name. This all documents will help you to prove your possession

Property tax receipts, EB bill, mutation of revenue records will help to prove your possession