Well- this is kinda a big question

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In a quick summary, I would say:
1.) Go cold turkey. I know it might be painful at first, but there are actually fewer arguments (as there are fewer times you turn the TV off), and you get into another habit, another way of living. Really. Cold Turkey. Move the TV out. Closet, garage, whatever. If it is sitting there, it is easy to turn it on.
2.) There is a "withdrawl period". For this, it helps to have a "schedule"- lots of things going on, less time going "I could just turn it on for a minute...". It takes about 2 weeks to really have a fundamental change, so I wouldn't go out and buy out the toy store, but I would write out a plan- a walk after dinner, events at the library, etc.
3.) Don't worry about guests. The kids will play, the grown-ups will talk. Overnight/visiting family- just warn them first. They will grumble and probably tease a bit, then they will get over it.
Good luck! Going tv-free was probably one of the most meaningful and important decisions we made as a family. And as the word of a former tv addict, I would NEVER go back!