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