I have always machine quilted on my Bernina 1530 for over 15 years. I agree that Harriet Hargrave HEIRLOOM MACHINE QUILTING is an excellent starter reference book. I have seen the book for sale on this website. I was able to attend one of her classes when she was in town.
Straight stitching diagonally isn't very hard and is called Cross hatching (really looks great as a background). Great idea to practice on cheater panels or charity quilts. It is just like cooking, your skills will increase as you practice. You will need a walking foot and a free motion foot to start.
There is a lot of methods to mark the quilt. Purple be gone is a temporary way of marking that should vanish after a certain amount of time. GREAT on light fabrics. I preferred Clover powder chalk markers for darker fabrics. I would always mark the quilt as I was pin basted the quilt.
You do need an area where the quilt will be supported when quilting. NEVER liked having to support the quilt over my shoulder. GOOD LUCK !!!
Example of Cross Hatching
[ATTACH=CONFIG]240255[/ATTACH]