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