I like to keep my bobbins clear so I use up left over bobbin thread when I piece things. Then, I use cone thread that is a neutral. Right now I have lots of bobbins with some thread on them because of raw edge applique that I used to make some Christmas gifts; I will have a piecing good time after the holidays. I use matching thread of quilt on the front of my projects. I like to use Bottom Line thread when I stitch in the ditch. I also like 30 or 40 weight thread to quilt my designs.