Steps for upgrading 2005B to 2007B

Hi

Im going to upgrade my client system to 2007B earlier it was in 2005B pl 42.

I dont know the exact procedure step by step which could help me to upgrade the system to 2007B.

Please give the procedure.

Steps that i followed are:

1. Installation of IRU server

2. Installation of IRU client

then there was an icon on desktop of SAP B1 IRU. I log in in the customer database and then page opened was "Internal Reconsilation Upgrade Audit Trial Report Filter". I selected all in from above and click OK then result was no result was found as a result of slection criteria

I think im not following the right procedure.Please help me in upgrading it starting to end.Your suggestion will be appreciated.

Thanks