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