• Hold down the space-bar to pan(drag) around.
  • Use scroll-wheel to scroll up and down.
  • Hold Shift and use scroll-wheel to scroll left and right.
  • Hold down the ⌘ key to zoom in and out with scroll-wheel.
  • Use ⌘ key in combination with - and = to zoom in and out.
  • Use the Z key to quickly zoom into a particular area.
  • Note that Page Up / Page Down switches between Pages.

Reference: http://bohemiancoding.com/sketch/support/documentation/10-canvas/

Keywords: sketch, canvas, navigation, keyboard, mouse.