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