I was reading around in some of the other posts but had a hard time finding a basic answer with detailed instructions on this. I’d like to custom label each choir staff in every system. I figured I may have to do this manually for every staff of every system since I deleted empty measures in an effort to have unison staves for SA and TB singing in unison for verse one, SA singing in unison for verse two, and then SATB splitting off into four parts in the middle of verse three and beyond, thus potentially creating a problem for Dorico’s automatic way of labeling choir parts. Using Mac OS, is there a way for me to label these staves individually in each system and will I be able to have the labels in the margin next to the staves? Below are pictures with details shown in red on how I’d like the staves labeled.
If you set this project up with two section players, and use divisi to split them out as and when needed, then yes you can customise the staff labels at each divisi change.
You can hide empty staves to hide the T/B staves when they don’t have content.
This was recommended to you in your earlier thread, so do go back and reread the advice given to you. (I see you commented on that thread more recently than this one: if you can try to keep your questions on the same topic to the same thread, or make it clear whether you still need help in a new thread, that would be very helpful just now as we are experiencing a high level of activity here!)
If any of it isn’t clear, feel free to ask for a follow up.
Hello. Ahhh, when you posted earlier on my topic of Combining unison choir voices, I had already written out the full score. I didn’t have the time to start up a new project. So instead, I erased the notes from the alto and tenor lines for verse one and also the ATB lines for vs two and hit the hide empty staves button. So now, with this, I believe I have no choice but to add a text box of some kind to each line or use another route to manually input the labels next to each line since divisi was not used in this score. Only frame breaks were used. Will your directions still work for this circumstance. In my next choral arrangement, I plan to start out with two staves.
No need to set up a new project entirely: you can fix that up in the current project, but exactly how depends on what you’ve done exactly, and I can’t know that from your description alone (on this forum, we strongly encourage people to share project files as much as possible, so the people helping you can see immediately what you’ve actually done; screenshots can help, but never tell the whole story).
For example, if your singers are currently held by single players, you can add section players, but don’t give them an instrument (leave them empty-handed by pressing Esc to close the instrument picker). Then, drag your existing voice instruments to the empty-handed players. Voila, now you have section players, which you can divide.
Or, rename the existing instruments to be S/A and T/B (or whatever formulation now makes sense) and show staff labels.
Hmmm I didn’t know sharing project files was a thing here. 
This forum introduction might be helpful:
I figured out a way to input those parts labels manually! however the way I did it I don’t recommend anyone do because of how time consuming it was. But it’s finished now. All of the information you have provided on this topic is very valuable information which I will be using in future projects as logically it will save me more time. I was just afraid I’d have to undo many things in an effort to follow those instructions to the tee. I appreciate all the time, effort, and patience the team and others have put into answering many of my topic creations, and I hope many Finale to Dorico individuals will find them useful. Thank you all!
FYI, which may be a comfort: I have been a party to this forum since before Dorico was released, and like quite a few others, I read every post. I have never, in more than eight years, seen a complaint that someone’s IP material was appropriated because they posted it here.