Hey Hellopin.
Hmm, difficult question there to really answer in full. With Impromptu there normally comes a quite good manual and loads of examples. I personally learned a lot on my own and, off course, from someone who sat beside me as I took my first steps in it. Another option is to go to your Cognos center hopefully nearby. There are some good training but they have a pricetag. And not a really small one either. But to put you on the road trough this medium would be quite difficult I think. For me that is...