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