how can you draw a square with 2 diagonal lines and 1 u in each quarter without retracing or picking pen up?

Answer 1

One what in each quarter?

The general answer to these questions if it can't be done in a straight forward way is to fold the paper over - go onto that then come back on another bit)

Answer 2

I think you need to add a little more description to this.

Answer 3

don't use a pen....use a pencil and do it however you want :-)