Here is some of my 3D modeling workflow in ZBrush that may be helpful.
i first started with a 3d concept model i made a while ago but had little appeal and i used very little planning for it. i then added an idea for concept ontop of the sketched model giving a better indication of direction. The little notes are guides so in ZBrush i can begin addressing the notes.
Then i blocked in major portions of the model trying to get proportions similar to concept. I used mostly the insert brushes and i tried to work on as low a polygon counts as i could (zremesher, halfing the poly count). (also is shown is the use of the zspheres in blocking out the back legs that i posted in an earlier post).
Then i sketched over the blocking refining the concept some more and making it a little easier to develop in ZBrush.
Then i worked the broken up pieces some more before I then merged them and worked on them some more using smooth, clay buildup, damian standard, move tool and a couple other brushes.
And here are some ZBrush hot keys i used that i found very helpful.
n show all subtools
o focal length
s size brush
shift snap ortho view
b enter brush mode
ctrl mask, click invert mask, click off remove mask
hold shift last circle move scale
q exit move mode
b,f,a brush flatten .. (the b,f,a means first press b then let go then press f then let go then press a)
b,c,b clay build u
b,m,v move tool
b,m,l lasso mask tool, b,m,k mask pen
b,d,a damian standard
b,i,w insert sphere
b,c,i clip curve
Hope this was helpful.