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