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