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