What are the best practices for integrating records between two ServiceNow instances?

[SeanKingston]

What type of items / attributes should be reviewed ...

[palanikumar]

Can you tell me what are you trying to integrate? are you looking for ebonding like integration or scheduled data transfer between instance? Have you finalize the approach like Rest API, Import Set, Remote Instance Spoke etc.. We can assist you if you share more details about this requirement