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