I hope I didn’t make this little tutorial too complicated to follow. I kept the shape on purpose simple.
I just love extracting parts of my mesh to create some sort of ‘hard’ surface objects. In Zbrush (many years ago) I used polyloops to do this; so when Nomad Sculpt 2.10 came out I was really stoked 
For those interested + tips to make tutorials easier to follow are always welcome.
the lasso step was the part i wasn’t sure about, good to see it validated into its own facegroup before extracting. did the extracted panels come out tidy as-is, or did you have to clean up the edges after?
Depending on the settings I get sometimes a weird extracting, but as soon as I adjust the height it goes away. Other then that it gets a clean boarder (see screenshots) .. because I don’t know if you own quadremesher, I showed also one on a voxelremeshed sphere. I hope that answers your question .. for sure don’t be afraid to play around with the settings and extract a FG several times to compare them. The original mesh is kept intact.
Thank you very much for these great
instructions!
Thank you for your kind words 
I am glad it helps.
