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