Straight out of the Ironman Training book so I wouldn't have to do any thinking of my own.

Technique workout

Warm up as:
300 freestyle
100 kick w/board
300 swim choice (I have no idea what that means...)
100 kick

Main set
10x100 as:
25 kick on stomach w/arms at sides
25 s2s
25 C/u
25 free
All with 20 sec recover

4x200 pull or swim easy
All with 20 sec recover

12x50 easy as:
25 kick on stomach w/arms extended
25 swim choice
All with 15 sec recover

Cool down.....