LPUB: Printing/Saving all submodels and their respective steps to 1 giant PDF...

[Jaco van der Molen]

I am not sure what you ask, but this is what LPub is for.
Reading your question I think your model does not have steps yet?
If not, add them and open the file in LPub.
A page per step and per submodel (with steps) should be generated.
Create multi step pages or convert submodels to callouts to get the instructions ready.
Then save to PDF!