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