A very 1930's look is to use three strands of embroidery floss and do the blanket stitch. I grew up with Little Dutch Girl and Little Dutch Boy (most people call them Sunbonnet Sue and his brother, but our family didn't for some reason) and they were hand done with embroidery floss. Not sure how Grandmother did hers so they lasted through about a million washings and being on kid's beds---but it worked fine. I haven't had as much luck and use floss only on wall quilts but then, I don't like to applique.

I use embroidery thread

I took an applique class at quilt camp many,many moons ago. The instructor suggested Mettler Silk Finish. Love it. Thread Magic comes in a small blue cube and will help the thead slide smoothly through the fabric. I think it helps with the wear issues too.

I use YLI 100 wt. silk thread and match the color to the piece that is being needle turned tack stitch appliqued. If I can't match exactly the piece I go with a darker shade as close as possible, because if you use a lighter shade it reflects the light and is more noticeable. If I don't have the right color in YLI 100 wt. silk, I use 60 wt - 2 ply (same as I use when piecing blocks for my miniature quilts.) Some greens, blues, beiges, browns in fabric colors can be appliqued with neutral threads in the taupes, beiges, greys (as appropriate to the fabric color)as they seem to be able to blend into the piece being appliqued.

As with any technique, we all have our favorites. I needle turn applique and use YLI silk thread. My 2 "go to" colors are #242 and #235 as they blend with anything. You don't really "need" to get a lot of different colors as the thread is buried and practically invisible. It's just fun to pick up some different colors. Have fun, whatever you do:)

For hand applique, I use dmc machine embroidery thread in 50 weight. The 60 weight, as 7dwarfs mentioned, might be better because it's thinner. I like this thread for applique. I find that neutral color thread, most of the time works great...but I do have some colors and use those if they match.

I use silk thread from Connecting Threads. I use a single strand and a straw needle. The thread becomes practically invisible. I found the silk off white blends well with all prints.

I bought one of those carousels that hole a whole lot of different colored spools and I lust love it. It has every color you need. Before that I used the silk thread because it disappears into the appliqué. Jan

I love the YLI silk thread, too. Great colors, too, if you find a shop with a variety.

This is what I do also ... with YLI silk. I usually just use either a light gray or a dark gray depending on the fabric since the thread really doesn't show.