Formal:
* "Hello, I am from Scotland."
* "Good day, I hail from Scotland."
Informal:
* "Hi, I'm from Scotland."
* "Howdy, I'm Scottish."
* "Hiya, I'm a Scot."
More casual (depending on the situation):
* "Aye, I'm from Scotland."
* "Right, I'm a Scot."
You can also incorporate a specific Scottish phrase like:
* "Hiya, I'm from bonnie Scotland!"
* "Hello, I'm from the land o' lochs and heather!"
Remember, the best way to say it depends on the situation and who you are talking to.