Hi,

At first you must know some basics regarding 3D digitizing.
You must take care to find the way how to prevent 3D foam to squeeze out betwen stitches at the end of object.

So first you must put few stitches just to hold the foam on the fabric.Then you should start digitizing ends of object where 3d foam could be able to squeeze out,the you put top stitches...i never use underlay by 3d digitizing,and only satin stitches for Top stitching.

Density should be between 0.20 and 0.30,dependable if you using 3d foam in thread colour.

And that's are some basic tutorials for start...

Good luck,
Bob