MS: Then: 12x25 on 20" rest - odds are easy (1, 3 etc) - the evens are fast!
Then 8x100 on 1:30 rest. These are fast and are Best Posible Average*.
Then 200 easy.
Next: Swim 12x75 on 15" rest.
(*) B.P.A. = Best Possible Average, this will be one benchmark set that you can do once every three weeks. The idea is to record the 8, 100's and average them. Keep the record and you should be slightly faster the next time.