How do I start oyster mushroom farming in a small room with low investment?

Oyster mushroom is the best mushroom for a beginner because it is cheap to start, grows on simple farm waste, and tolerates a wider temperature range than button mushroom. You can start in a small clean room of even 100 to 200 square feet with a few bamboo or rope hangers for the bags. The usual substrate is chopped wheat or paddy straw, soaked and then pasteurised by hot water dip or steam, drained, mixed with spawn, and packed into perforated polythene bags. Keep the bags in the dark for the spawn run, then move to light with high humidity and fresh air for fruiting. A small home setup can often be started in a modest range of a few thousand to a few tens of thousands of rupees depending on whether you buy a boiler drum, racks and a fogger. Keep everything clean, because contamination is the main beginner problem. Get a local crop calendar and the right species for your climate from your KVK or DMR Solan.