Answer
As suggested, find your volume by dividing your weight (in newtons) by water's weight density. The weight density of water is $9800 \frac{N}{m^{3}}$ (page 230).
The buoyant force is the weight of the displaced air, so multiply your volume by the weight density of air. On page 271, the latter number is given as $12 \frac{N}{m^{3}}$.
As an example, if your weight is 490 N, for example (roughly 110 lb), your volume is (490/9800) = 0.05 cubic meters. The buoyant force is (0.05)(12) = about 0.6 N, roughly the weight of a large egg.
Work Step by Step
This is discussed on page 271.
