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