Generally the legs are scissored with shears, not thinners. Blending is done with thinners, where the short body hair meets the longer leg hair, just above the elbow area and into the elbow. When you scissor the legs, comb the hair straight up from the foot all the way to the top, and neaten all the edges in parallel lines. Then comb the hair out and away from the dog, and neaten again. This will take alot of practice before you get the nice, even columns you see in pictures. Its not something most people can do the first few times they pick up shears. You want parallel lines, and columns for legs. I usually round the foot first, and start my lines from there to the elbow, then work around the leg. If you make the foot too tight though, it will mess up your lines, and if you leave the foot too hairy, you will mess up your lines. Practice, practice, practice.
I hope that helps give you and idea of how to get started?
