Well to start in planted straight into the finale pot, but you should fill it all the way up to the top and leave about 1/2 inch gap from the top. I then indent the top, so it dips and makes watering easier.
The soil should be quite loose, and lol no you dont need t put soil in holes, they are the holes for air pruning and that where the water will piss out off, and believe me sometimes it does.