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