Find out if the builder will let you do it.
Flexible conduit is the easiest, e.g. Carlon Resi Gard. Orange conduit is for low voltage only. Some long straight runs could be done with gray ENT.
Your local electric supply houses carry flexible conduit.
The blue flexible conduit is rated for line voltage, but can also be used for low voltage. The electrical inspector could get nervous if he sees the blue, as he wants to make sure all the line voltage wiring is in place for the inspection. But, many times the builder will allow you to run the conduit/cables after the electrical inspection and before drywall goes up.
Install LV cables outside of the conduit; the conduit is for futureproofing (adding new cables that were forgotten, or some new technology arrives).