Regardless of where you got your corn, now that you've got it, you have to malt it. Malting helps start the coversion of insoluble starches into simpler starches and sugars. This conversion will be continued in the mash (see below). The idea behind malting is to trick the seed into thinking it is time to start growing. Upon sprouting, the seed will begin converting the starches meant for long-term storage to a simpler form more suitable for use during the initial growth phase. The malting process turns maize into jora.
If you're dealing with kernels still on the cob, peel the husks back, remove the silk, and hang them in a warm place for at least two weeks (the longer the better). The kernels should be dry and loose on the cob. I found that the drier the ear is, the easier the kernels are to remove.
When dry, remove the kernels using whatever seems to work (a twisting motion works well for me, but watch out for blisters).
Soak the kernels in water for 2 days. With one particular type of corn, the kernels sprouted for me while still soaking. With another type, they did not. There doesn't seem to be any reason to soak for more than 2 days. After a day or two, you will notice signs of 'fermentation' (production of gas bubbles and a not unpleasant odor). Because of this, you want to drain, rinse, and replace the soak water at least twice a day.
If you don't see evidence of sprouting while soaking after 2 days, don't worry. Remove the corn and place in a container that allows drainage. When using corn I've grown, I often deal with small enough quantities that a large colander works well. Larger quantities are accommodated by a plastic tray with holes drilled in the bottom. I use a kitty litter box for this. The depth of the bed of corn does not seem to be too critical, but it should be relatively shallow (about 2-3 inches) to discourage the growth of mold and to make turning the corn easier. This is a problem particularly with large amounts of corn that are not easy to rinse and turn. Cover the colander/cat box with a damp dish cloth to keep the kernels from drying out.
Rinse the corn at least twice a day. The corn also needs to be turned at least twice a day. This makes life tougher for mold and it also seems to have the effect of making the rate of sprouting more even. Once removed from the soak, sprouting proceeds pretty quickly and I think the buggers like some air. Again, different kinds of corn behave differently, but you should see the roots grow to one inch within a few days.
Note that the roots will appear first and will get to be an inch or so before the acrospire begins to grow. Don't confuse the roots (long, thin, and white) with the acrospires (shorter and thicker than the roots, and greenish/yellowish in color). Keep the sprouting kernels from sunlight as this could have the effect of allowing the acrospires to become green and bitter. Allow the acrospires to reach a length of 2 to 3 times the length/height of the kernel.
Depending on the corn, your germination rate will vary. I have seen apparent 100%, 95%, and 50% germination rates with several different types of corn. I'm sure there are probably many reasons why there is so much variance. Perhaps it depends on the health/maturity of the corn. You'll get a higher rate of germination if you age the dried kernels for several months.
Also, generally growth is not very even. If you need a project, you can pluck out individual kernels when their acrospires reach the desired length and dry the entire batch in stages. Or wait until some are very long and most have sprouted and dry the whole batch at once.
When the acrospires reach 2 to 3 times the length of the kernel (4 to 7 days), their growth should be stopped. This can be accomplished by spreading them out in the sun. This works surprisingly well and is my preferred method. Or, if your oven can maintain a low temperature, that can be used. Spread the baby corn on a cookie sheet and bake it at 130F for about 8 hours. A food dehydrator can also be used.
When the malted corn appears to be completely dry, it probably isn't. I store mine in brown paper bags so that it can (hopefully) continue to lose moisture. I've had minor trouble with weevils when storing jora for more than six months. After a month or so storage in a paper bag, I put mine in the fridge until I'm ready to use it in the hopes that this slows the bugs down.
When dry, you have jora.
Another method of "malting" corn produces muko instead of jora. Muko is made from corn that is not sprouted, but instead dried, ground, and the flour masticated. Traditionally, this task was performed by groups of women and children. Once moist, the ball of flour is flattened against the roof of the mouth with the tongue, and the cake is removed from the mouth and allowed to dry. Amylase enzymes present in the saliva convert the starches in the corn and this was the method by which the highest quality chicha was once made. Not too much chicha de muko is made these days because of the amount of labor involved, though I have talked with several people who make chicha this way at home. Muko could be substituted directly for jora.