There are numerous ways to express the notion of "without worrying." If you want to convey the same meaning in a different way, you can use words such as carefree, relaxed, untroubled, stress-free, undisturbed, easygoing, calm, and serene. These terms indicate a state of mind that is free from anxiety, stress, or concern. For example, instead of saying "I am doing this without worrying," you can say "I am doing this carefree" or "I am doing this in a relaxed state of mind." Regardless of which one you choose, the aim is to depict a sense of calmness that allows you to approach the task at hand without feeling burdened.