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