Smell

In the vegetative stage, most cannabis tends to make an unnoticeable smell. But once flowering really kicks in, the smell can range from tame to “WHAT IS THAT SMELL?!” Luckily, this can be easily corrected with several products like carbon filters, or odor neutralizers. Additionally, you can try growing cannabis strains that are known for low smell. The goal is to make sure that the smell stays within a few feet of your plants.

Sound

When buying any kind of electrical device, look up reviews on the product to make sure it runs quietly. A low-quality exhaust fan or air pump will cause people to be suspicious since they make lots of noise and typically run all day and night.

Sight

To the outside world, it should appear as if you’re doing everything as normal. As paranoid as it sounds, you should assume that anyone who sees you doing growing related activity will know what it is and report you.
Move any growing equipment at night so you’re less likely to be seen
Be careful about what you throw in your trash. On the rare occasion that I do throw cannabis trash(like stems) in a trash can, I usually cover it in food trash so no one will want to go through it
Pick a couple days to walk around your house at a few different times of the day to see if anything stands out as suspicious. Example: Super bright yellow light(HPS) coming from a window at 11:00pm.
Be a good neighbor! A lot of people think of cannabis growers as criminals. When you continue to act like the intelligent, well-mannered, amicable person you are, your neighbors natually become less suspicious!
Don’t look like a stereotypical stoner! There’s nothing wrong with Rastafarian clothing or wearing red/green/yellow all the time, and it’s your right to dress and act as you wish! Just remember that police, nosy neighbors, and marijuana haters are likely to ‘judge a book by its cover’ and harass a person based on their clothing…regardless of how unfair that is.

Electrical Safety

A Google search for “house fire marijuana” will yield stories for events in at least 7 cities (in the first 2 pages alone) where people have accidentally burned down their cannabis, their home, and everything they own in electrical fires. Most electrical safety mishaps can be prevented with a few healthy habits:
Only purchase quality equipment. Quality parts means fewer failures, which means fewer fires started. Fire is bad!
Keep water and other liquids below waist level and electrical equipment above waist level. Even if this isn’t always possible, it will help to accomplish the real goal: keeping water and electrical devices separated.
Clean up all spilled water. Having a few towels or a roll of paper towels handy makes this a breeze.
Don’t overload your circuits. If you live in an older house, you probably don’t want two 1000w HPS lights and high powered exhaust fans running from one room. Sticking only to what you actually need will help you in this department. For example: for indoor growing that’s strictly for personal use, a single 600w HPS will keep you in constant over-abundance all year, every year.

Know the Law

In the U.S., many states have their own laws on how marijuana is treated. Some states will send marijuana users to jail for years, some will give them counseling, others will just give a fine, and some do nothing at all.

However, it’s important to remember that marijuana is still illegal according to U.S. federal law, as well as the law of most countries.

It’s imperative that every grower spend a little time making sure they know the laws that apply to them to help minimize the risk of being prosecuted.

U.S. residents, see NORMLs page on marijuana laws state-by-state: http://norml.org/laws

I recommend staying away from digital ballast most throw high amounts of radio freguencys and cut alot of devices down am/fm radios satalites internet routers. Not discrete at all or if you have neighbors.