One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,7)(5,8)(9,10,13,16)(11,14,18,22)(12,15,20,24)(17,21,19,23)(25,26)(27,35)(28,33)(29,31)(30,42)(32,39)(34,36)(37,48)(38,47)(40,44)(41,53)(43,49)(45,52)(46,50)(51,55)(54,56)(1,3,6,2)(4,7,5,8)(9,11,13,18)(10,14,16,22)(12,19,20,17)(15,23,24,21)(26,31)(28,40)(32,43)(34,42)(35,47)(37,51)(41,50)(52,56)(9,12)(10,15)(11,17)(13,20)(14,21)(16,24)(18,19)(22,23)(25,27,36,49,29,38,30,39)(26,32,42,47,31,43,34,35)(28,37,50,56,40,51,41,52)(33,45,53,55,44,54,46,48)(1,4,6,5)(2,7,3,8)(12,20)(15,24)(17,19)(21,23)(25,28,29,40)(26,33,31,44)(27,37,38,51)(30,41,36,50)(32,45,43,54)(34,46,42,53)(35,48,47,55)(39,52,49,56)(1,5,6,4)(2,7,3,8)(11,18)(14,22)(17,19)(21,23)(26,31)(27,38)(28,40)(34,42)(39,49)(41,50)(45,54)(48,55)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.