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