I'm not replying as an expert. However, I did just go through my first B&M experience and have some advice.

1) Play the lowest buy-in limit game they offer for a half-hour. Play tight and spend you free time trying to make sure you know what's going on with the dealer button, house etiquette, table chatter, etc. A big mistake in a 3-6 limit game will cost you a few BB's. Better than making your first mistake for your whole NL buy-in. After you get comfortable with pokering in a casino, move over to your NL table.

2) Boredom becomes an issue playing live. Don't be the intense guy who kills all the fun, that's negative EV and no fun. Find something to do with your time when you're not in a hand or you'll end up with too many hands. Popular choices are chip shuffling (definitely plus EV, as the newbies will think you're a professional and the retired whiners will think you're a young punk who needs a lesson), or (more usefully) ghosting other player and guessing their hole cards before you see them.

3) From reading these forums, you would think that every other pot in a B&M cardroom has three hands declared dead, a physical altercation, and a heart attack. It's more like every fourth or fifth pot. Seriously, though . . . watch your hole cards, be vocal about your action ("I check", "I raise" etc.), and everything should be fine. If you're friendly to the table, they'll keep you in the game. If you have fun, you'll make more money too.