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