There are a lot of little gotchas in the transition to live, but it is a lot of fun an well worth it.
Stack sizes and pot sizes are obviously not instantly available in digital form, so you need to ensure you aren't over-committing to a hand because you misjudge pot equity or the SPR.
You can do silly things like mucking the BB in an unraised pot. I did this my first time out and have seen it happen to others.
While some of the players will be very good, on average casino players haven't spent the time reading multiple poker books
and discussing hands online. Therefore, you have an advantage in this regard.
Most importantly... HAVE FUN AND GOOD LUCK!