An oxygen delivery apparatus wearable by user includes a frame including nose pads connected to a bridge portion, an oxygen inlet defined by one of the nose pads, an oxygen inlet defined by the frame, and a hollow channel contained by the frame. The oxygen inlet and oxygen outlet are in fluid communication via the hollow channel. The frame can be formed as a monolithic structure using additive manufacturing. A nasal prong can be connected to the oxygen outlet such that a prong outlet of the prong is in fluid communication with the hollow channel. The prong outlet is positioned within a nostril of the user during use of the apparatus. A method of fabricating the frame includes obtaining measurement information for at least one of a head feature or facial characteristic of the user and generating a digital model of the oxygen delivery apparatus using the measurement information.