HI April
I use a size 10 or `12 between needle. but when I started hand quilting years ago, i started out on an size 8 needle.
You can use what ever size hoop is comfortable for you, or not use any at all. And I like Coats & Clark all cotton thread, just my choice. It is a little thicker than using a polyester thread, but I like the looks of the stitches more.
when you look at threads, there will be one that will say for hand quilting, and any of them will do.
Hand quilting is so relaxing and you should just relax, and enjoy it. Don't worry about how small your stitches are. the most important thing to practice is getting them all the same size. Also learning how to "pop" your knots into the middle of your quilt to hide them. Have fun with it!!!!
I use a Fons & Porter mechanical pencil to mark with. It comes with dark and white lead. And you can also use masking tape. I also use 1/4 in tape, to quilt 1/4 in from the seams.