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