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