1. Always test your water before you start. pH and tds (total dissolved solids) meters will let you know what kind of water you are working with and what needs to be done to it. (filter or ph adjustments)
2. Most plants will need their medium (what the plant is growing in) and water to be in the 5.5-7.0 range.
3. If your tap water is above 300 ppm (parts per million) this might be a sign of hardwater or polluted water. You might want to consider a reverse osmosis filter or using distilled water.
4. Make sure to assess your gardening space before you decide on what technique to use. (do you have easy access to water?, a place to drain water?, is there a way to assure proper ventilation?, if something floods will it be costly?, is there enough space to work in?, are there enough electrical outlets? how high are your ceilings? (plants cant be too close to the grow lights). Knowing these things will help you set up the proper system that fits your needs.
5. If you are growing indoors you will need to seal the room with a reflective material to maximize the light available to plants. Cover the floors as well if you don't want to get the floors wet or dirty.
6. Setting up all ventilation and electrical should be done first before anything.
7. Hanging lights with ceiling hooks and light pulleys will allow you to raise and lower lights as you please.
8. Inline fans and oscillating fans are recommended for proper circulation and ventilation.
9. Humidity must never be allowed to go over 60%. This promotes mold and will reek havoc on an indoor garden. Ideally 40% humidity is where your environment should be but as long as its not over 60% plants will be fine. Humidity gauges are a must. Proper ventilation will help with humidity but in some cases a dehumidifier will have to be used.
10. Temperatures can range anywhere from 50-90 degrees but ideal temps for most plants will be 65-80 degrees.