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