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