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