If you have the SnapDrive software installed - it can create the LUNs for you. So you would just need to have the volumes available on the filer. With a CIFS share created. Then, on the SnapDrive software, just step through the Create Disk options and it'll create and add the disk for you.
There should have been a UserGuide link available where you downloaded the SnapDrive software.
Download SDW from now site. Logon the iscsi initiator in your windows host, Under start menu you will have windows iscsi initiator, run that and logon initiator(connect). In SDW under transport protocol settings, add your filer with proper credentials (use http or https as the transport protocol). In SDW under iscsi initiators, iqn should get listed, now you can connect the LUNs that you already have on the filer by rightclicking on the host and say connect lun and follow the setps.