The easiest way it to select it using the info tool. In version 6, you can change the way it is highlighted by pressing F9 to view the symbology editor, then edit GP 305. If you want to highlight multiple parcels, then set the layer as the Active layer by right mouse clicking on the layer in the layer control tool, and choosing active layer off the menu.

The other alternative is to copy the parcel into the edit layer if you want to keep the highlighted parcel for a while. To copy the parcel, select it using the info tool, click the add button, then click save.

Once you have added a the new parcel you may require to change its colour or appearance. Refer to Help -> Contents -> “Changing The Way Your Maps Look By Using Symbology” for instructions on how to do this.