Normally, you’ll find a Guid already created in SQL or something similar. If you need to create a Guid in your C# code, here is a fantastic little site that will generate a random Guid with a few specifications you control.
Options you can choose:
choose to create up to 2,000 Guids
specify upper or lowercase
add surrounding curly braces
There are a few more options but I don’t use them and don’t want offer an incorrect explanation. For more detail on extra options, please review the documentation on the guidgenerator site.
This nifty little tool helps if you need to create some generic guids to test your code before connecting to actual data.
If you just need to create a random guid to insert into SQL through your code at runtime, you should use something like this:
cmdInsert.Parameters.AddWithValue ("@guid", Guid.NewGuid ());