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