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