Hi Vimal
Kindly follow the steps
1. Install the Windows 2008 server with latest service pack and windows updates from Microsoft site
2. Configure the Windows 2008 Cluster environment, Kindly refer the link
Failover Cluster Step-by-Step Guide: Configuring a Two-Node File Server Failover Cluster
3 Install the Oracle DB in windows cluster environment
4. Restore the Database from production server to DR cluster DB
5. SAP system copy by using the SWPM in Cluster environment
refer Installation Guide link - http://service.sap.com/instguides
6. SAP Post installation steps and Check with function team
7. Enable the Oracle log shipping
Time duration depend up you DB size this action you can perform during the working hours(its not require any down time for primary site)
Regards
Sriram