Hi welcome to TG

What you need is a drawing - if you don't have one you have to make one.

If you make one from scratch it helps a lot if it is a vector drawing made with xtreme/illustrator/coreldraw/inkscape etc.

You can use photoshop/paintshoppro etc too - but they are not vector programs.
This may not matter as far as the drawing itself goes, but if you wish to use xara3D you would then need to vectorise the shape first, which can be tricky

Hope this helps