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