I do all my quilting on my Viking Sapphire 830 - it has the larger throat space and I do up to King Size 120 " x 120" regularlyon this machine. I do not do it in sections and havenever had any specific instructions other than what I have read here at the QB or on the internet. I use one of three methods to sandwich my quilts.
1) Spray baste with 505 in the red can
2) Use Elmer's washable School Glue to secure the sections together
3)Use Hobbs 80/20 Fusible batting and iron it with a slight steam setting
By using the above methods, I can start quilting on the outside edge and work in towards the middle. No one told me I couldn't start on the outside and work inward and it works the best for me. It makes it easier for me to hand the larger quilts and because my layers are so secure there is rarely and I mean rarely a pucker. I always wash my quilts prior to gifting so the glues wash away and everything it clean and ready to go. I made a few scrappy doll quilts to practice on when I started my FMQ and gave them to the granddaughter to play with. I don't do anything fancy mostly meandering, micro stippling and I am expanding into stensils.
Good luck andpractice makesfor almost perfect
