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