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