#1 Always assign new posts to a category and also create your own categories:
At the beginning this seems unimportant, because there are only a few posts on the workspace and everything seems to be clearly arranged; but if someone is looking for a certain info after 2 months, the categories help enormously to find it again. Subsequent assignment is also possible, but can only be done by the person creating the post.
#2 Assign meaningful file names BEFORE uploading under "Files&Links
Under "Files&Links" you can't upload a description for linked files, only the file name itself appears, so a meaningful naming of the files is extremely helpful; of course before uploading ;)
#3 Place important information within easy reach
I had the problem that there are some infos (tips&tricks or etiquette or hints) that I wanted to keep always well accessible in the workspace, so they should not get lost in the long list of posts. My tip is to write this info e.g. in an Etherpad (https://jitsi.kh-berlin.de/etherpad/) and then create the link to this Etherpad as an additional tool in the workspace:
// "Manage Workspace"
// "External tools": Add link from Etherpad