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