Looking at the C Major scale for an example:
C D E F G A B
1 2 3 4 5 6 7
I'll just extend it to two octaves to help with the above explanation:
C D E F G A B C D E F G A B
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Ionian
1 2 3 4 5 6 7
C D E F G A B
Dorian
2 3 4 5 6 7 8
D E F G A B C
Phrygian
3 4 5 6 7 8 9
E F G A B C D
And so on...
Hope this helps.. if not, let us know.