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