There are many ways to spy on someone. How much spying you can do depends on how much access you have to the person's home, car, and computer. You also must first determine what you want to find out. You'll need a different approach depending on your goal.

If the person is a stranger whom you suspect of illegal activity, you can follow him, research him, and try to find out more about the person's activities. Alternatively, you can hire a private detective to do some of the spying for you.

The Internet is a great place to begin spy activities. Simply searching for a person's name online can give you a lot of information. If the person is involved in forums or social networking sites, it's easy to follow them and their activities.

Surveillance and physical tracking can be done by car or foot. You'll need mental preparation first. Make sure you have an excuse if you get caught. Don't follow close behind. Walk without making noise. Blend in to the surroundings, but wear something that disguises you a bit, like sunglasses or a hat, so that you aren't immediately recognizable or memorable. If you're spying from a window, turn out the lights and stand back from the window a bit so that you aren't visible. Binoculars and night vision goggles can make it easier to see details.

To find out where the person goes, you can use a GPS tracking system device. The device is small and unnoticeable and easily attaches to a vehicle. You can find out where the person drives, where the car gets parked, and how long it stays there. The tracking systems record information that you can view later. Some have real time features that allow you to go to a website and view where the vehicle is at any time.

Bugs are one of the oldest forms of spy equipment. You can get bugs to plant in a room or a telephone. Some are available that look like everyday objects like clocks or pens. Most record audio and video so that you'll have to retrieve them later, but some allow you to listen remotely with headphones. Hidden cameras are similar to bugs but record images. Modern hidden cameras are small and easy to conceal.

There are plenty of devices available that allow you to spy on computer activity. Popular devices plug into a computer and record keystrokes. There is also software that monitors chats, emails and keystrokes. Some software can be installed remotely, so that you don't even need access to the computer.

Keep safety in mind when spying on someone. While it's best to keep your spying activities private – others can slip up, gossip, or leak information inadvertently in other ways – if you're heading into dangerous territory, it's best to let someone else know what you're doing. Some types of spying activity is illegal, so find out what local laws are before you plant tracking devices, bugs or other surveillance equipment.