Using Webservice in Dashboard

Hi SCN,

I need to create a Dashboard based on webi report through Webservice option.

1. Please let me know how to create the same.

2. How to limit the data set in Webi and performance tuning so as not to get more data into Dashboard.

3. Any performance tuning methods .

4. How to pass prompt values from Dashboard to Webi.

5. Any best practices.

Regards,

Nagaraj