Bushes and half-standards require as little pruning as possible. Do this in April to avoid infection by silver leaf disease. Cut out dead, diseased, badly placed and crossing branches completely, the more you cut back, the more unproductive regrowth will follow.
Dwarf pyramids and fans are trained in a similar way to apples and pears but you should delay the winter pruning until April. Pinch back shoots which are not needed to 6 leaves. When other shoots have reached the required length pinch these out as well. Then in late summer, after fruiting, shorten all pinched-out shoots by a half.