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