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