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