One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,8)(4,6)(5,7)(9,10,13,16)(11,14,17,21)(12,19,20,15)(18,24,23,22)(25,26,30,33)(27,35,37,50)(28,32,40,48)(29,42,44,34)(31,43,46,38)(36,51,39,53)(41,56,55,49)(45,54,47,52)(9,11)(10,14)(12,18)(13,17)(15,22)(16,21)(19,24)(20,23)(25,27,30,37)(26,31,33,46)(28,39,40,36)(29,43,44,38)(32,47,48,45)(34,50,42,35)(41,52,55,54)(49,51,56,53)(1,3,5,4)(2,6,7,8)(11,17)(14,21)(18,23)(22,24)(25,28,30,40)(26,32,33,48)(27,36,37,39)(29,41,44,55)(31,45,46,47)(34,49,42,56)(35,51,50,53)(38,52,43,54)(1,4,5,3)(2,6,7,8)(11,17)(14,21)(18,23)(22,24)(27,37)(28,40)(31,46)(32,48)(35,50)(38,43)(41,55)(49,56)(9,12,13,20)(10,15,16,19)(11,18,17,23)(14,22,21,24)(26,33)(31,46)(32,48)(34,42)(35,50)(45,47)(49,56)(51,53)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.