Position your purchased planting box in a flat place.
Fill the box with washed sand until white mark or at level with the overflow.
Put the geotextile on top of the sand.
Fill the rest of the box with soil, making sure it is overfilled, as after a few days the soil will settle and fall a couple of centimetres .
Cover your soil with mulch (loose hay/straw or sugar cane).
Fill the box with water through the system inlet (higher pipe) until the water comes out through the overflow (side lower pipe).
That is it! Now it is ready to be planted.
Give a good traditional watering to the box to start creating the soil ability for a week.
Finally, it is recommended (once a year) to turn overflow anti clock wise until horizontal level is reached. Let the water run for a couple of minutes to wash the bottom of the system to reduce excess salts and minerals accumulated.
And once a year a linseed oil or old cooking oil application will keep your cypress protected!