I would like to know what are the different steps or tasks to do in order to set up new Marketo instance for business.
Best practices to follow in the implementation, specially for Marketo stand alone without any integration with CRM.
That is a GIANT question.
There are a few threads here on Marketo without CRM. Things to consider:
Very long list of possibilities here. Please take a look here: Marketing Rockstar's Guide to Marketo - How to Use Marketo as well as topics at Etumos, RevEngine Marketing, Perkuto, TPG, etc before you begin building.