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