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)(11,12)(13,17)(14,15)(16,20)(18,19)(21,22)(23,24)(25,26)(27,34)(28,32)(29,31)(30,33)(35,40)(36,39)(37,38)(2,3)(6,7)(10,15)(11,16)(17,24)(18,21)(25,27,30,29)(26,31,33,34)(28,35,36,37)(32,38,39,40)(1,3,5,2)(4,7,8,6)(10,15)(11,16)(17,24)(18,21)(28,36)(32,39)(35,37)(38,40)(1,4)(2,6)(3,7)(5,8)(9,11,14,16)(10,12,15,20)(13,21,23,18)(17,22,24,19)(25,28)(26,32)(27,35)(29,37)(30,36)(31,38)(33,39)(34,40)(9,12)(10,16)(11,15)(13,22)(14,20)(17,18)(19,23)(21,24)(25,26)(27,31)(28,32)(29,34)(30,33)(35,38)(36,39)(37,40) involution — undirected(9,13,14,23)(10,17,15,24)(11,18,16,21)(12,19,20,22)(25,29,30,27)(26,31,33,34)(28,35,36,37)(32,40,39,38)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.