Absolutely. Definitely practice with a real board before going to a tournament. Looking at real pieces is much different than looking at a 2D board!
Playing in a real chess tournament

hey, cool. which time controls did u have? in case of long chess the ultimate tip is to analyze the whole game with your opponents directly after finishing the games, especially with higher rated opponents. sometimes you can even make friends this way. have a good day!

To me a rated tournament has much higher highs and much lowwer lows than playing chess online. The fact that you actually see your opponent is a bigger factor (to me at least) than any difference between looking at an online 2d board and pieces vs. 3d board and pieces in "real life".
Another big difference is when you play a game online you can chose the range of ratings that your opponent will be in. I have been in many tournaments where my opponent was over 500 points either weaker of stronger than me.Even in the tournaments online here there is usually not that large of difference in ratings.
Of course "real life " tournaments have the added disadvantage of the cost and inconvience of both travel and entry fee. For a few there is an added benefit of the possibility of prize money but for most it is unlikely.
One thing to remember though....just because you are playing online there still is a real flesh and blood opponent who you are competiting against!

In contrast to the other experiences mentioned here, I thrive when playing speed chess in front of a crowd. There's no question that the physical v virtual format is fundamentally different psychologically.

I love playing OTB since u can actually feel much more pressure and the stakes are much higher compared to online chess.

I traveled to Chicago to play the US Open in 73. I haven't played a tournament game since, the vagaries of life demanding that I receive a paycheck. But it was the greatest week of my life, and without a doubt, the most interesting group of people I've ever seen. I ate everything in sight and still lost 5 lbs. Try it guys.
(Didn't do too well, faulty plan.)
I had a similar experience. I play shorter time control affairs. G/30 is my standard OTB game. The first time I played, the pressure of keeping a scoresheet and hitting the clock totally threw me, and I lost to some kids with ratings under 400. Since then, as a TD, I've watched it happen to others as well. I've seen people with lots of experience at Chess end up with ratings of 315P5. Usually, at their second tournament, they are in line for the "biggest upset" prize, because they got rid of their opening day jitters.
Even after I settled down and got the scoresheet thing under control, I was surprised at how tired I was at the end of a day of OTB Chess. It can be quite draining.

I did pretty poorly in my first OTB tournament. Looking forward to better results on my next. I'm optimistic because I play OTB and online each week.

Have played in only 4 otb games, everything else here on line.
1) This score sheet thing, is this something you MUST do? or is it just good practice to do?
2) When you first meet, what do people usually say, just hello? or good luck? "Good luck" seems not appropriate, since there's not much luck involved.
I look forward to my first OTB tourny. . . yes, I need to have a chessboard by my computer.

Have played in only 4 otb games, everything else here on line.
1) This score sheet thing, is this something you MUST do? or is it just good practice to do?
2) When you first meet, what do people usually say, just hello? or good luck? "Good luck" seems not appropriate, since there's not much luck involved.
I look forward to my first OTB tourny. . . yes, I need to have a chessboard by my computer.
If you have a problem with rules, you must be able to recreate the board. Otherwise people will cheat on you and you can't do anything about it.

yeah it is strange at first, i've found that people play totally differant over the board too. i've got a tourny next week, gonna be fun

This sounds just like what happens when you play poker online for a long time, then try to walk into a casino and dive into a tourny. Everything im reading brings me back to that.

try to avoid chess.com for a bit once i made silly mistakes in a real tournament because my eyes just lost it as this was real and not 2d
Have played in only 4 otb games, everything else here on line.
1) This score sheet thing, is this something you MUST do? or is it just good practice to do?
2) When you first meet, what do people usually say, just hello? or good luck? "Good luck" seems not appropriate, since there's not much luck involved.
I look forward to my first OTB tourny. . . yes, I need to have a chessboard by my computer.
USCF rules require all players to keep score. There is an exception if the player does not know how to keep score, but that is usually applied only for young children in scholastic tournaments. If a player is not keeping score, the TD may assess a penalty. The exact penalty is unspecified, but is usually a time penalty for the player who is not keeping score.
When either player has less than 5 minutes remaining on the clock, neither player is required to keep score.
(I think, but don't take this to the bank, that the 5 minute rule is void if playing with a 30 second increment. In that case, scorekeeping remains mandatory in all cases.)
There are also some special cases for handicapped players and players with religious objections, but those are very rare cases.
After playing lots of online chess I recently played in a real over the board chess tournament with real people and real chess boards and pieces. It was MUCH harder than I expected. After playing so much online chess, my brain got bamboozled when I had to make decisions looking at a real physical chess board and pieces. Even though I got my butt kicked it was a valuable learning experiece. Has anyone else had a similar experience?