It is so easy to use. My favorite is the sewline TRIO it has a white and black fabric pencil and a tracer point. All you have to do is turn to click out, which one you would like to use.
I used the black fabric pencil here
The black was easy to erase with the fabric eraser. When using the black fabric pencil be careful not to use a lot of perisher it will be harder it erase.
I used the white fabric pencil here and was very happy with how it worked and looked.
To get the white to erase you had to really work at it, but it did come out.
I used the fabric glue pen and is by far the best I have ever used. The glue rubbed off nice and went where I wanted it to go
I folded over the fabric and it stayed down. The glue dries clear and is water soluble. If you have any question about any sewline product please feel free to ask