I use OneNote. Here is how I do it.
Each File is a Family
Each section is a person
Each page contains something that pertains to that person, e.g. one for birth, one for death, one for marriage, etc. There are no limits as to the number of files, sections and pages that you can add.
I also have a section up front for each family called Overview. Here I have a page for fellow collaborators including name, email, user name on Ancestry if appropriate, etc. All fellow collaborators can see who is copied on the file. Overview might also have research notes, theories, ideas tried and failed as well. A failure is just as important as a major breakthrough (although it doesn't feel that way).
Since OneNote is in the cloud, it is perfect to share with cousins which I have done. I live in the USA but I have shared family files with newly-found British cousins.
You can cross-reference pages within OneNote. A marriage certificate is a good example. You can also insert almost any object into OneNote and move it around as you please. A copy of that marriage certificate that I found on Find My Past can be downloaded directly into OneNote. I include maps that I found on the internet since I am not very familiar with the territory (I love maps).
Finally, there are UTube videos on this subject that I found helpful.
Good luck!
