the 20mg@1mg is cheaper than buying the small pills. the larger pills work out cheaper per dose, but are harder to split.
that should be plenty, the pills are scored in the center just snap em in half. .5mg e3d until the problem goes away or you run out
.
some people prefer a higher dose up front, to combat prolactin gynecomastia.
.5mg ed for a 10 days (5mg)
.5mg e2d for 10 days (2.5mg)
.5 mg e3d for the rest (12.5mg)