well, i made this for a member of my forum who was new.. so maybe someone else can use it too,.... i doubt it though
First, You Select The Eraser tool from the Menu Heres a picture:
ok now you have selected the eraser tool.. ok...
Now you can erase the things you dont want so the picture you want is left..
to manage the size of the rubber do the following;
Click the arrow next to the size of the rubber on the topbar
Now choose the size by moving the scroller..
the picture tells you which one
now start rubbing so you are left with the render
The End