It is recommended to print this from the side, which will produce the best results and does not require any support structure by the design of the structure.

This holder can be easily attached to the aluminum wall of a shower cabin as long as it is no thicker than 3mm. For thicker walls or other attachments methods, like screw mounting the model should be modified accordingly.

I printed with 0,2 mm height with PETG and 20% infill. The precise setup should not be particularly relevant due to the structure of the model, though I would not recommend PLA due to the fact this is meant to hold wet material. Infill is needed only in a few corners, such that the amount of infill is likely not a relevant factor.

In the second version I also added a holder for the textile headband.

If you want a clip to attach those tubes to furniture you may want to check out https://www.printables.com/model/246904 as well.