Make a resource holder class now. Global SFML resources will more often than not lead to crashes due to undefined destruction order.
Thor (http://www.bromeon.ch/libraries/thor/tutorials/v2.0/resources.html) has an excellent resource holder class and the SFML Game Development (https://github.com/SFML/SFML-Game-Development-Book/tree/master/02_Resources) book has some code for one as well.
what would a function in main that uses the Game Development example look like. Would it look something like this?
ResourceHolder exampleTexture;
sf::Texture cake;
exampleTexutre.load(cake, directory)