Using Adobe Photoshop to mock-up a responsive website

programming web dev
1

Hello,
I work for a university and I need to create a responsive website for one of their departments. The web team uses Foundation for creating webpages.
I am not as skilled as other designers when it comes to mocking up a website using css frameworks, so instead I want to use Adobe Photoshop because I am more familiar with it. I am also going to use a grid to layout out the website elements in Photoshop. Then I will use the Photoshop mock-up as a guide for creating the layout in Foundation.
Two questions:

  1. How large should the canvas be in Adobe Photoshop if I am creating a responsive website? I’m going to create a mockup that shows what the website would look like on the PC.

  2. Should I still use the 960 grid download for Photoshop for mocking up a responsive website? And if so, then which set of columns work the best for responsive design - 12, 16 or 24?

Thanks!