Writing a response paper
Start by reading the papers.  A structure may suggest itself -- for example, four separate sections, or a structure organized by theme.

If you're not sure, after reading the papers, then try writing a couple different outlines.

If you're still not sure, you could perhaps take a look at a couple of strong response papers (written, obviously, about different papers, but hopefully in an area you can relate to)?

You can also go see your instructor in office hours, show him or her your outline and ask for guidance.