One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,3,4)(6,10)(7,11)(1,2)(3,4)(6,10)(7,11)(13,14,17,18)(15,19,20,16)(5,6)(7,8)(9,10)(11,12)(14,18)(16,19) involution — undirected(6,10)(7,11)(13,15,17,20)(14,19,18,16)(5,7,9,11)(6,8,10,12)(13,15)(14,16)(17,20)(18,19)(5,8)(6,11)(7,10)(9,12)(13,16)(14,15)(17,19)(18,20) 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.