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