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