You may have noted the two plugs on either side of the valve in the detail. These allow access for installing a future liquid fertilizer injector for applying fertilizer using the irrigation system. These plugs are optional, however I strongly recommend installing them, especially if the valve controls a drip system. Calcium and other minerals in the water can build up on the emitters and plug them with time. A weak acid solution can be injected into the water to dissolve the mineral deposits by using a fertilizer injector .
Some people also like to place a hose bib on the upstream side of the valve where the plug is.
This allows a garden hose to be attached for supplemental watering or whatever. Simply wrapping them in plastic tape is not sufficient. Multi-strand wire can carry more voltage than single strand wire and is more flexible, making it idea for the short leads on the valve where both of these features are useful. But multi-strand wire has one big disadvantage in this situation. When the water gets into the solenoid it destroys it.