Qyery desigining confusion

Hi Gurus

I am new to BI, and in my learning phase am trying to design a query using BEx query designer in BI7.O.

I have created plan cube and actual data cube, have also created multiprovider using this 2 cubes. Now I am confused whether I should proceed with query designing, or I need to create DSO, and thn proceed with multiprovider using this DSOs for planned data and actual data and than design a query.

If possible, can anyone send me steps for query designing and reporting in BI7.O

Please help.

Thanks in advance