For showing you want a 40. This can cause irritation though pretty easily but it shows the skin which is what you want. You could do a 40 on feet and a 30 on the face if there was irritation. I've also heard that clipping while they are damp is good to prevent irritation when using blades this short.
I use a 10 or 15 for practice (and we aren't showing yet anyways) but even freshly groomed you can tell it isn't short enough because he is black all over instead of having grey skin.
I use a 10 or 15 for practice (and we aren't showing yet anyways) but even freshly groomed you can tell it isn't short enough because he is black all over instead of having grey skin.