There are a few items you will need to connect your speakers to your television. Since most speakers are not powered, you will need to install a power amp. You will also need speaker cables so that the sound will reach the speakers from the power amp and audio cables to send the sound from the television to the power amp itself.
Connect your television to a power amp using an audio cable. You can use a basic left and right stereo audio cable for this if your TV has an analog audio out. If you look on the back of your television, you should see red and white RCA jacks that are labeled "audio out." Plug the corresponding colors of the audio cable into the jack. Plug the other end into the stereo receiver where it is marked "audio input." There will be multiple audio inputs so it is best to plug your cable into the one marked "TV"; that way, this will make remembering which input you used very simple.
There are also digital outputs available on more modern televisions that will send multi-channel digital sound to your television. Use a digital cable to send this sound, and it will be processed by the receiver and separated into multiple channels for the surround-sound experience.
To hear the sound from your television, you must have a stereo receiver or power amp to amplify the sound sent through your audio cables. There are many styles and brands available from Philips, Onkyo and Sony. The features and power included can vary from 100 watts per channel to over 1000. There are simple two-channel stereo models to receivers that can feed audio to seven separate channels, including a sub-woofer and a center channel. Depending on the sophistication of your television, there is a stereo receiver that can maximize the quality of sound heard for movies and digital programming.
Connect your speakers to your receiver using speaker cables. There are many types and sizes available, and the standard size cable is 16 gauge, but any gauge can be used. Speaker cables can vary in price from a less than a dollar per foot for generic store branded cable to several hundred dollars per foot for audiophile cables by Audioquest. The merits of such expensive cable are often debatable, but most audiophiles claim to hear a difference.