This is the completed box, growing Miriacle fruit & Mango (cuttings) with capsicum, alpine strawberries, butternut pumkin, and brocoli.
This cost me nothing apart from some hydroponic mix.

Move on to step one to see what you need..

Step 1: What You Will Need

The parts you will need.

1. Foam Box (Ask ur local supermarket, they throw them away and will usually give them to you)
2. Sharp Knife or Thin Saw (To Cut holes in foam)
3. Large Black Plastic Bag (At least one)
4. Pots (Hydroponic pots are better, but any with good drainage holes will work)
5. Hydroponic Mixture - Any Should Do..
6. Hydroponic medium (Perlite/Vermiculite) Or others
7. Seeds or Plant
Optional 2..
ABOVE STUFF &
600 ml bottles
Drill
Seeds or plants

Option 3..
ABOVE STUFF &
Baby Formula lid
Scissors
Growing Plant Only
Requires no medium

Step 2: Cutting the Holes

To Start,lets cut holes in your foam box lid, using the pots base as a cutting guide. I find cutting with a stabbing like motions reduces risk of breaking it.
This will make a hole too small, but that what we want to start or you risk breaking the lid. Once you have a small hole run the sharp knife around the inside of the hole till the pot fits tightly.

(in between cutting holes remove pots and place on a firm ground)
You want the pots to sit tightly in the foam holes, but don't force them in if the hole is too small, you will snap the foam lid.

At least 2 inches of pot showing through the bottom, that will sit in the water by a centermetre or so.

Note you should use pots that have the same depth, as it makes it easier to line up the bottom of the pots so they have equal depth of water each.

Step 3: Filling the Base

OK, now with your base..
Line it with a black plastic bag, This is cause styrene used to make polystyrene can be absorbed by plants, making them unsafe for consumption and eventaully the plants will be sick.

Mix the hydroponic mix as per instructions (there are 2 many)
Mine suggests
(1/4 strength for the 1st week)
(1/2 on week 2)
(Full Strength after that)

Fill it 1.5 - 2 inches from the top depending on the depth of the pots used and the amount you have protruding through the lid.

Basically, until the roots can out grow out of your pot then you simply add less water and let the protruding roots suck up the water, not the medium in the pot, but to start with the medium needs to suck up the water so make sure that the pots are sitting in the water by a centimeter.

P.s. Once a week top up the fluid, water is fine, just remember how many litres and you can add hydroponic formula later

If plants drown or get sunlight on their roots they will droop, if they have too little nutrient they yellow starting with leave's veins.
Basically slighty more water is easier to manage, add to much nutrient and you'll kill the plants very quickly.
Hope that helps.

Step 4: Check Water Level & Start Planting

Put on the lid, and check water level, should fill till there is at least 1-2 cm of water.

Then there are a few options...
Easiest
1. fill with moistened Perlite or Any hydroponic medium..
2. Plant seeds or plants into medium.
3. Just remember to check the water levels.

Removeable Recycled Bottle Option. (Picture with Strawberry)
1. Using the top 1/2 of 600ml bottle
2. Drill holes in the lids
3. Screw of lids, invert 1/2 bottle fill with moistened medium.
4. Place into pot, making sure that the cap sits in a little water
5. Plant Seeds or Whateva.

Tricky
See Picture attached.. (Brocoli & Pumkin)
1. Using the lid off a baby formula (soft plastic kind)
2. And a pair of scissors make one cut from edge to the centre,
3. Make a small circle in the centre,
4. Put a plant into the hole in the centre and using 2 screws,
5. Screw the lid into the foam.
6. Then i taped up the clear lid with green eletrical tape to stop the light getting to the roots which can kill it.
7. So this grows with no medium at all!!! Quickest growth, not suitable for all plants, and occasionally you have to lift the plant so it doesn't strangle itself in the hole as it grows.

P.s.
Make sure you wash plants roots, if they have previously growing in soil.
You don't want soil in your roots at all..
:)