The structure of sestinas is very interesting and quite complex. Elizabeth Bishop's sestina demonstrates the pattern well. It starts with house, next grandmother, child, stove, almanac, then tears. the next stanza starts with tears. tears was the last word in the previous stanza. Next, house which was the first line in stanza one.

Searching on google I found the following:

Stanza 1: 1 2 3 4 5 6
Stanza 2: 6 1 5 2 4 3
Stanza 3: 3 6 4 1 2 5
Stanza 4: 5 3 2 6 1 4
Stanza 5: 4 5 1 3 6 2
Stanza 6: 2 4 6 5 3 1
Tercet: Variable.

http://en.wikipedia.org/wiki/Sestina