Growing marijuana indoors requires the following steps:

1. Choose the right strain: Different strains have different growing requirements, so choose one that suits your setup and experience level.
2. Set up a grow room: This can be a spare room, closet, or tent. Make sure it has good ventilation, light-proofing, and a stable temperature between 70-85°F.
3. Purchase grow equipment: You’ll need grow lights, a grow tent, pots, soil, nutrients, a hydroponic system, and a fan for ventilation.
4. Germinate the seeds: Soak the seeds in water overnight, then plant them in soil or a hydroponic setup. Keep the environment warm and moist.
5. Provide adequate light: Use LED grow lights or HID (high-intensity discharge) lights to simulate sunlight. Keep the lights on for 18-24 hours a day during the vegetative stage and reduce the light to 12 hours a day during flowering.
6. Control temperature and humidity: Maintain a temperature of 70-85°F and humidity of 40-60%. Use fans and air-conditioning to regulate the environment.
7. Fertilize the plants: Use a balanced fertilizer and adjust the nutrients as needed throughout the growth cycle.
8. Monitor plant growth: Check the plants regularly for signs of stress, disease, or pests. Take action promptly to prevent any problems from affecting the final yield.
9. Harvest and dry the buds: Wait until the trichomes have turned milky white before harvesting the buds. Dry them slowly and cure them for 2-4 weeks to enhance their flavor and potency.

Remember, growing marijuana is illegal in many countries and states, so check local laws before starting.