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