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