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