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