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