One vertex per element, one color per generator, with an edge from x to x·s.
(2,6)(7,8)(9,10)(11,14)(12,16)(13,17)(15,18)(19,22)(20,21)(23,24)(25,26,31,30)(27,32,37,36)(28,33,35,38)(29,34,40,39)(1,2)(3,7)(4,8)(5,6)(9,11)(10,14)(12,19)(13,18)(15,17)(16,22)(20,23)(21,24)(25,27,31,37)(26,32,30,36)(28,29,35,40)(33,34,38,39)(1,3,5,4)(2,7,6,8)(11,18)(14,15)(19,24)(22,23)(26,30)(32,36)(33,38)(34,39)(1,4,5,3)(2,8,6,7)(9,10)(11,14)(12,20)(13,17)(15,18)(16,21)(19,23)(22,24)(25,28)(26,33)(27,29)(30,38)(31,35)(32,34)(36,39)(37,40)(9,11)(10,15)(12,19)(13,18)(14,17)(16,23)(20,22)(21,24)(25,29)(26,34)(27,35)(28,37)(30,39)(31,40)(32,38)(33,36) involution — undirected(9,12)(10,16)(11,19)(13,21)(14,22)(15,23)(17,20)(18,24)(25,30,31,26)(27,36,37,32)(28,38,35,33)(29,39,40,34)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.