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