Do you want to modify the global php.ini file to accommodate a script you are installing.
You have a script 'myscript.php' that requires the following settings according to the documentation -
1. register_globals need to be turned on
2. safe_mode needs to be turned off
3. enable_dl needs to be turned on
In this example the script 'myscript.php' resides within your public_html/ directory.
1. Open up notepad on your computer and add the following
register_globals = On
safe_mode = Off
enable_dl = On
2. Save that file with the name 'php.ini'
3. Upload that file to public_html/
Now you have a custom php configuration!