Systemwide Defaults
1. Launch Wolfram and set up any changes to the front end that you need. For example, you may want to modify default file locations, language options, or menu settings.
3. Copy the file $UserBaseDirectory/FrontEnd/init.m to the directory $BaseDirectory/FrontEnd.
4. Launch Wolfram and create a new file.
5. Add any Wolfram Language commands that should be evaluated on startup. For example, you may want to add a function definition or display a message at startup. Enter all the commands in the same cell, separating commands with semicolons.
6. Make this cell an initialization cell by selecting the cell bracket and then choosing Cell ▶ Cell Properties ▶ Initialization Cell or using the keyboard shortcut Ctrl+8.
7. When you have finished making your changes, choose File ▶ Save and select Wolfram Mathematica Package from the Save as type popup menu. Then save the file as $BaseDirectory/Kernel/init.m.