There isn't really an easy way to do it. Unless, of corse, your variables are in arrays... Then it's a cinch.
Without Arrays:
Open App.Path & "ErrLog.txt" for output as 1
Print #1, "Variable1 Value:"
Print #1, Variable1
Print #1, "Variable2 Value:"
Print #1, Variable2
Print #1, "Variable3 Value:"
Print #1, Variable3
And so on...
Close 1
With Arrays:
Open App.path & "ErrLog.txt" for output as 1
For i = 1 to NumberOfValuesInTheArray
Print #1, "Array(" & i & "

Value:"
Print #1, Array(i)
next i
Close 1
You may need to edit the pathname somehow so that it doesn't overwrite itself, and you may need to change the file number if you're already using "1".
That's about all I can give you, hope that helps. I'm not really an expert, I just know the simple stuff.