How Can I Turn My Vizio Television Into A Computer Monitor?

I just got a Vizio television at Sam's Club. It's a huge tv- 55 inches!
I want to make it into a computer monitor, especially for when I have friends over.
Could you please tell me what I need to do so? I have a laptop which i would prefer to use, but also a computer that is across the house from the tv.
I need to know what I need, what to do with it, and where to get it.
Thanks so much! All help is appreciated!