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