What is the schedule for a seven team league?

Answer 1

That depends on how the competition is intended to proceed and how many rounds it needs. For a knockout competition, it would go something like
1) A v. B
2) C v. D
3) E v. F
4) G has a bye.
5) loser 1 v. loser 2
6) winner 1 v. winner 2
7) loser 3 has a bye.
8) winner 3 v. G
9) loser 5 v. loser 3: playing for 6/7 position.
10) winner 5 has a bye: 5 position.
11) loser 6 v. loser 8: playing for 3/4 position.
12) winner 6 v. winner 8: playing for 1/2 position.

where G was the winner of the last competition, or the highest (or lowest) seed.
For a round-robin competition, it may proceed in a much more complicated fashion; one such way may be placed here at a later time.