Hooks are printed separately to achieve good strength, so instant glue is required to assemble the parts.
Optimal printing direction is shown below:

In case you want to know, my boxes are printed with no top and bottom shells. It not only reduces printing time, but also looks cool. If you use Prusa Slicer, the setting is under “Print Settings” > “Layers and perimeters” > “Horizontal shells” > “Solid Layers”.
I use the grid infill pattern. Feel free to try others.
I use onshape (free version BTW), which is a powerful CAD tool with a web interface.
You can access all parts and their dimensions using the following link:
The author marked this model as their own original creation.