Hi! I always cut my binding at 2.5 inches, then fold it in half.
My guess is you will need 7 to 8 strips cut width of fabric for your twin quilt. I always buy 1 meter or 1 yard and keep the rest for my stash.
I join my binding strips on the diagonal, to reduce the bulk in the seam.
I sew my binding to the back of the quilt, then do mitred corners, and fold it to the front.
When I stitch the binding on the front I use a zipper foot so I don't slip and can get nice and close go the edge of the binding, I ensure my bobbin thread matches the quilt backing.
I love doing machine binding as I feel it gives extra durability to the quilt and won't fall apart when washed in the future. Good luck!