This has bugged me both in Okular and Adobe Reader: They are capable of displaying facing pages next to each other, but both display the first page on the left by default and all the following as they come, so individual pages are on the wrong side in standard books, where page 1 is on the right. Annoying if you want to check layouts.
Adobe Reader solution: View->Page Display->Show Cover Page During Two-Up
Okular solution: Settings->Configure Okular…->General->Centre first page
I think all of this could be a little more intuitive.