What are the best practices of creating new SQL Server instance on SQL Server Clustering 2008 R2 and migrating a database with high transactions?
You can start from this list from Jonathan Kehayias.
Can you elaborate on "migrating a database with high transactions"? This is very open ended question and not sure how to address this. There are lot of good practices to follow here.
There are so many other things here but it takes a while to list them all and it depends.