Superior threads have a number of videos that could help you and they would have correct terms for you.The companies market them under different brand names here.Try to go for something called misty fuse if you want a softer feel.Some of the badge making ones are very stiff. I find that I mostly use one that is called 'vleisofix'.It is quite useful for a variety of purposes. There is also a fusible thread which you sew around the edge of the applique and then iron onto the background to keep it in place whilst you stitch it in . It means that you don't have it heavily stuck down and it remains soft and pliable.