What requirements should a website layout meet for 2560 resolution?

Question

User interface

We were given the task to render an existing site under 2560. What should be done first?
Thank you! :)

Answer 1

What should be done first?

Open photoshop, create a canvas with a length of 2560.

Answer 2

Resolution 2560 does not exist in the wild (well, or it must be a 25+ monitor).
Most likely they want retina layout from you.

Answer 3

Maybe after all @2x?