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