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)(11,14)(12,16)(13,21)(15,18)(17,23)(19,24)(20,22)(25,26,31,28)(27,32,29,33)(30,34,38,36)(35,39,37,40)(2,3)(6,7)(9,10)(11,14)(12,16)(13,17)(15,18)(19,22)(20,24)(21,23)(25,27,31,29)(26,32,28,33)(30,35,38,37)(34,39,36,40)(4,8)(6,7)(9,11,15,12)(10,16,18,14)(13,19,23,20)(17,24,21,22)(25,27,31,29)(26,33,28,32)(30,35,38,37)(34,40,36,39)(1,3,5,2)(4,7,8,6)(9,12,15,11)(10,16,18,14)(13,20,23,19)(17,24,21,22)(25,28,31,26)(27,32,29,33)(30,36,38,34)(35,39,37,40)(9,13,15,23)(10,17,18,21)(11,19,12,20)(14,22,16,24)(25,29,31,27)(26,32,28,33)(30,37,38,35)(34,39,36,40)(1,4)(2,6)(3,7)(5,8)(9,14,15,16)(10,11,18,12)(13,22,23,24)(17,19,21,20)(25,30,31,38)(26,34,28,36)(27,35,29,37)(32,39,33,40)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.