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