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