At the end of each growing season, there is usually a natural weak point in the fleece where it would break off. This weak point is called the "rise".
Shearing is a bit of an art. You get better at it as you become more confident that you know the shape of the sheep and are not going to snip anything but wool!
My shears are quite big and extremely sharp. Blunt shears are more likely to cause nicks because they do not cut the fleece cleanly and can slip. By keeping the blade parallel to the sheep's body you get a neat even job and are unlikely to injure the animal. The weight of the fleece falling away from the body opens up the next line of fleece to cut.
Some of the girls were lovely to shear, but when I came to do my 8 shearling tups it was a different matter. They have been turned out on a nature reserve for months and virtually untouched. They are BIG, well muscled from climbing over walls and escaping, curly horned and very woolly. Although a few rooed, most were a nightmare to shear because it is their lamb fleece (very long and thick) and having had no trauma (such as raising a lamb) most had no natural break in their fleeces.
They look a little bald, but I'm sure Rosie and pals are happy with their new styles really!