how can I see POST methods in raw HTTP that my computer sends to a page?

that's it

isn't there a way to see the raw text file that my browser sends to a website when I do a POST method?

something like:

POST /path/script.cgi HTTP/1.0
From: frog@jmarshall.com
User-Agent: HTTPTool/1.0
Content-Type: application/x-www-form-urlencoded
Content-Length: 32
home=Cosby&favorite+flavor=flies

Thanks!