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