Valves for our applications are normally fall under the 5/4 port 4 way 3 position setup. As in this picture below trying to explain the ports. Its of a spool valve to get backward and forward control of a hydraulic circuit. I recommend going with the rotary valves shown above. They have the same fluid control but tolerances are easier to obtain than a spool setup. Also I recommend a closed center position so your hydraulics will not creep. How you make each valve is up to you. Individual depending on your application or together on a manifold with pressure and return circuits built in like RCP57's really nice manifold set up.
Ps Pressure from your pump
Pr X2 Return circuit. Combined on a rotary valve. Seen on the above pictures.
Pa and PbYour lines to both sides of your cylinder.
