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