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