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