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