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