To manually draw whatever kind of shape you firstly need to create a sketch. In the jobs’ tree on the left select the magic wand icon and click on “Sketch”
A new sketch will appear with a default name, Sketch# (where # stands for a progressive number).
To draw something you have to select the sketch, then click on “Draw” which is on the toolbar above and choose what you want to draw. You may select directly the shape you want from the Draw toolbar.
Here is an example of drawing a line:
Select the Sketch, click on the line icon and draw it on the plan.