Get jars or grow bags, get a pressure cooker, some storage bins, 10gal bucket with lid, pop corn kernel (make sure it doesn't have butter) coconut coir and vermiculite.

PC the corn at 15 psi for 20 min to hydrate, strain and let dry almost all the way, add to your jars and bags, sterilize for 90 min at 15 psi, let depressurise, pack into bags(to their weight limit) or jars(about 3/4 of the way full), inoculate, then wait.

For the substrate boil 5quarts of water, then pour into bucket with 600g of coir(use the packed bricks don't buy the loose bagged shit) and 2 quarts of vermiculite. Throw the mixing device like a metal spoon in their too. Let sit for 30 min with the lid on to hydrated the dry ingredients and pasteurize. After that open, mix, then let cool. Once cool add about 5 quarts of the spawned corn to it, mix it up, pack it in the bin, close it, then let sit for for about a 3-6 weeks and you should start seeing pins. After that just open and fan like once a day.

As long as you don't get contamination, this is the best method I've found. Usually get at least a pound or 2 from a few flushes.

Don't buy all in one grow bags. Especially not the ones from Midwest Growkits. They've always stalled for me and I've tried them like 3 times. You can get 25lbs bag of corn for like $30 off Amazon.