hold shift will constrain the proportions of the shape and you will end up drawing a square. The other way is to direct select any shapes you want to combine with the Direct Selection tool (A) and copy > paste them into the vector mask you want to combine them with. Make sure that you select the vector mask and not the layer.
Add the first ring of the notepad with the Rectangle tool.
The next tip is to select the first loop with the Direct Selection tool and copy + drag the next few into place by holding down the Option key. When you get to the last loop you may need to tweak the body of the notepad. When you design miniature icons thereâ€™s sometimes a bit of tweaking that needs to happen as you work. Because there are a limited number of pixels you will often find that balancing the designs will require constant tweaks to the shape. This is another reason that while the Pen tool can give you similar results, itâ€™s not as editable as vector shapes.