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