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