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