Will be arriving at DUS and staying at Holiday Inn Express in Dusseldorf North.
What is the cheapest way of getting there, without killing myself?

And then, need to know how to get from the hotel to Koelenmesse (Cologne) via train.

If anyone could answer these questions in detail (i.e., which train to take, which way to walk--treat me as stupid), I would sincerely appreciate it.

Thanks!