You've got the details a little bit off, but the basic principle right.
On a ball or pin lock cornie keg, there are two posts - a gas and a liquid. So you'd connect the gas to the gas (in) post and the liquid to the liquid (out) post and you're all set. Pressures are a different matter - if you're gonna set to 30psi, you're going to do so for no more than 24 hours, then drop down to serving pressure (11 or 12psi). If you're going to just wait a week or two, 11 or 12psi for the duration is the right neighborhood.
In a sanke connector, there's a gas in connector and a liquid out on the sanke tap - you'd hook both those up, then hook that sanke tap up to your filled keg, and let it sit at that same pressure setting described above, and you're good to go.