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