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