There are a lot of different wool battings. And it does puff nicely. At least the wool batting I used which was Hobbs. Good to do a test piece. From what I know, you just can use usual threads like So Fine 30. Glide 40, although some quilters I know also use Silk 100 if they are doing things like micro stippling. I only have used it a few times and I thought it was delightful and it felt wonderful after quilting. Be sure to read about whatever brand of wool you have. Some shrink more, some require closer stitching. If I recall correctly, the Hobb's wool bat only shrank about 3%. Some high loft batting may be difficult to quilt on a domestic machine because it is too high. Your 770 is a high shank machine so hopefully it will do OK, and don't forget to use your settings on your machine. actually, I do believe the machine will adjust pressure and stuff if you tell it what you want to quilt on. Check the manual or help button.