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