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