What strategy did he remember as he went down into water?

Dear Student,
 
Douglas, when going down in the water, decided to make a big jump when his feet touched bottom. His strategy was to make a big spring upwards, clear the surface of the water, lie flat on the water and then, strike out his arms and thrash the water with his legs. He was planning to thus paddle to the edge of the pool and get himself to safety.
 
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