How to get soap out of iPhone display?

Soapy water went through my iPhone 5 through speaker or something then i put it to dry and it works perfect but through my display I see it all stained and the background looks all dirty when looking at a white page such as google and it gets in way of pics. How can I get this off?

Have it repaired by Apple (advised) but if you want to save money (risky) open it up yourself I guess? Search for people with the same problem as you ob Google: D