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