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