Use the config:publish artisan command
php artisan config:publish wysiwyg/ckeditor
And the asset:publish artisan command to pubish the assets
php artisan asset:publish wysiwyg\ckeditor
When this command is executed, the configuration file will be copied to app/config/packages/vendor/package where they can be safely modified.
include in app/config/app.php in array of Autoloaded Service Providers
'Wysiwyg\Ckeditor\Providers\CkeditorServiceProvider'
To test if is OK, you should create a route:
Route::get('/ck', function(){
echo CKEditor::editor('textarea_name','<h1>Teste</h1><p><i>Teste</i></p>');
});