I had a fun conversation with @tmuth today: I attempted to distill my entire tips & tricks ‘sermon’ down to a single suggestion.
For productivity, I suggest every user get comfortable with Document Tab Groups.
Clik here to view.

Tab Groups are shown concurrently in the SQL Developer desktop display
So if you want to work on a stored procedure while you browse a table, right click on your document tab, and add a new document tab group. This allows you to SEE more than one editor at once.
You can add as many as your monitor will support in terms of display real estate.
You can drag and drop documents from one group to another.
If you have an external monitor, I suggest you become familiar with ‘float’ing editors as well.
Clik here to view.

Right-click to ‘float’ and to ‘dock’ it back to primary desktop space.
I apologize for the rehashed material, but I read recently that someone needs to hear something like seven times before it ‘clicks.’