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