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