I created a new package as a .sty file. I want to be able to use it in all of my documents.
I followed the instructions on the MacTeX website. I located my Library folder in Macintosh HD using Command + Up. It had a TeX folder, but no texmf folder, so I created one. In fact, I created the following subdirectory (at least that's what I think it's called) :
~/Library/texmf/tex/latex.
I added my file, mystyle.sty, to this folder. Then I attempted to compile a minimal document using the command \usepackage{mystyle}. I got the error message File 'mystyle.sty' not found. What should I do?

latex, create a subfolderMystyle, and in it add the filemystyle.sty. I'm not sure if you can directly addmystyle.styin the root of thelatexfolder. Does this advice help? – quark67 May 03 '19 at 21:17mystyle.styis in the folder~/Library/texmf/tex/latex/Mystyle– May 03 '19 at 21:20.styfile in the same folder as your.texfile? Is the compilation correct with.styhere? – quark67 May 03 '19 at 21:31texhashon the local folder. – Alan Munn May 03 '19 at 22:16texhashin Terminal and clickedEnterbut it didn't fix the problem. – May 03 '19 at 22:17texmffolder in~/Library, i.e., in the library folder of your home directory, and not/Library? In the Terminal, what does the commandls ~/Library/texmf/tex/latexreturn? – Alan Munn May 03 '19 at 22:17SystemandUsers. It is in the second highest level after the one withMacintosh HD,Network, etc. – May 03 '19 at 22:18/Library, the Library folder at the root of your HD. You should be using~/Library, the Library folder in your HOME folder. That Library folder is normally invisible. To open it in Finder click on th Go menu and hold down the Option key to see a menu item to open that folder. You can make it permanently visible if you HOME folder but opening that folder, typing Cmd-J, an checking the box about it. – Herb Schulz May 03 '19 at 22:27