Choose a suitable container
The container should be strudy, waterproof, rodent proof, and at least 30 cm. tall.
Just
about any used pail or bucket should be okay.Try anything
sturdy, readily available at home. 
You can use a plastic crate
or any 
laundry basket or tub. You can also fabricate
something out of waste wood, or plastic material. In any case, do not use a metal container, like an old bucket etc. The metal container can become unbearably hot in summer, and kill your worms. You are going to fill up 4-5 layers of at least 50 mm each, this will weigh about 6 to 8 kilogrammes. So,
make sure your container can carry
that much weight and volume. It should be sturdy enough, so
that rodents do not gnaw through the container. And it should be
capable of withstanding exposure to rain and sunshine. Also, make
sure that you can lift the container, with all the material,
yourself. And make sure it will fit into the place where you want
to keep it, till the colony develops fully, and is ready for
harvesting.
Scrub and wash the container thoroughly several times with fresh water. Do NOT use soaps or detergents. Worms are very delicate creatures. Any residual salts or chemicals can hurt them pretty badly.
Drill holes for draining out excessive water
Earthworms enjoy moist surroundings, but they cannot live under water. So make sure you do NOT drown them in excessive water. Water should drain out easily from the container. So, drill
many holes of about 5 mm dia like
this, on the base of the container.
Prevent worms from escaping
When you have drilled holes
like this, you can be sure some worms may also wriggle their
way out. You have to stop the fugitives from escaping. You also
have to stop other insects from infiltrating into the colony.
You must block the base. Take a sheet of thin synthetic sponge
(the kind used for wrapping delicate objects while packing
them), and a sheet of nylon mesh,
like this. . First lay
the sponge on the base, covering all the holes. Useful Tip: If you soak the sponge in water, it will be easier for you to flatten it and spread it out evenly.
Then, spread the nylon mesh over this sponge. The mesh will block the worms from escaping. The sponge will let excess water pass through and yet keep the base wet. The baby worms are so slender, they can slip between the holes of the nylon mesh. The sponge will gently block them from escaping further. Adult worms cannot slip past the mesh, anyway.
Then, spread
a layer of two sheets of plain
newsprint newspapers. These layers will also keep away all
intruders -- ants, crawlers, centipedes....etc. Sprinkle some
water, and ensure that the bed is wet but not drippping.
You are now ready to use the container to create your own worm
colony. The newspaper will decay gradually, or be eaten away by
the worms. This will give enough time for all the matter to
settle down and get consolidated.
Prepare the base bed
First, spread a layer of cow dung of about 40 to 50 mm. Over this, spread a layer of decaying organic matter (composted leaves), about 40 to 50 mm.Populate the colony
Release
a handfull of earthworms, gently, into the container, over the
organic matter.
Cover up with protective layers
Add one more layer of cow dung and then a layer of decaying vegetative matter.
These will
cover the worms, keep them warm, and protect them from predators.
Finally,
cover the container with a nylon mesh, and tie it
up securily. This will help all gases to escape from the container,
and avoid foul smell. It will keep the container well ventilated and
cool. It will avoid flies and protect the worms from flying
predators (birds). It will also prevent your worms from crawling away from the
top of the container.
Your container will finally look like this :
It would be a good idea to document the date when this colony was created, and pack the paper in
a plastic pouch. You can add
other relevant details like the source of the starter worms,
quantity of worms etc. Place the pouch on the top of all the material, in the container. Update this document regularly, as the colony progresses. This will help you keep track of your experiment.
Place the container in a
cool, shady place, well-protected
from predators, like this,
or like this.
Earthworms are the ideal pets one can adopt at home. They do not bite or sting. They do not need any special attention or care, unlike other pets. They do not need to be fed, because they feed on the decaying stuff you have put in the container. It is a great pleasure to
watch your worms enjoy themselves
and grow 
like this. Very soon, they will start multiplying.
IMPORTANT Do NOT stir the container. Do not poke with a stick or shovel, or pitchfork. Do not shake the container, or rock it violently. Earthworms are very delicate and fragile.
