Adding Drawing Markups
The "Drawing Markup" toolbar in iSkysoft PDF Editor 6 Professional allows you to have the option to insert particular shapes into your PDF files or draw free-form shape in your PDF document with ease.
Draw Basic Shape on PDF Page
Once you've imported a PDF file to this program, click on the "Comment" button and then you will see the drawing markup toolbar. Full ranges of options are available: Rectangle, Oval, Cloud, Polygon, Connected lines, Line, Arrow, Pencil and Eraser. You can click on the shapes you wanted and place it to the part you want to add. Click on "Eraser" button to erase what you have already created.
Freehand Draw PDF Files
If you want to draw in a PDF file, you can click on the "Pencil" icon under the "Comment" tab. Then you can move the cursor to draw free-form lines in PDF files.