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