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