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