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