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