In some embedded system designs, a multi-layer PCB cannot be used, so a two-sided board must suffice. In such situations, try to make a sheet pattern for the Vcc and GND wiring on the whole area – or as much of the entire surface as practical. Typically, though, you won’t be able to use a whole-area pattern. In that situation, we recommend that you use a half-area pattern in which Vcc and GND are symmetrically patterned on the facing layers, overlapping wherever possible.