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