If they are mere utility methods, then I would generally prefer to make those methods static ...
This answer is not wrong, but static methods have some limitations in flexibility. It
might be worth keeping a real object and abstracting its creation:
Factory.getInstance().someMethod();
Now you've removed your hard coded dependency on the implementation class. Factory could return any subclass of MyClass, or better yet any implementation of MyInterface.
In the beginner forum I wouldn't recommend building this kind of flexibility all the time, but keep it in the back of your head somewhere. If you bump into something like that, figure out what kind of flexibility the author was trying to keep open. I know I've made a couple classes with all static methods that I regretted later because they were too hard to change.