When I first started machine quilting back in 2004, I looked all over for a mathematical way to figure out borders. Something that would work all the time on every border. Unfortunately, I could not find one. I thought I would share with you how I figure out an undulating spine that goes around the entire quilt. I have found that it is best to mark these before you load the machine on the frame.
Click here for the video of how I figure out this spine!
You can use this spine for ferns, flowers, feathers… really any thing or maybe just to divide up your border or space to do different fills on either side. I’d love to know how you measure and mark your borders. Leave it in the comments below!
Lisa H Calle's Blog 
In a class with Judy Severson, she recommended using dinner plates! A quilt top was laid out flat on the floor and a series of dinner plates was placed along one leg of the quilt, corner to corner. The undulating line was drawn over and under the plates to define the spine. It’s still my favorite method, because I can move the plates around easily to get a good idea of spacing before I draw my line. But I am not a stickler for precision and using measurements to place the spine is probably better for accuracy.
I cut tissue paper or tracing paper the length and width of the area I want to cover.then I fold it into the number of repeats I want…example into 3rds or 4ths. Then I draw in one section, trace to the other sections and copy to my quilt. If the quilt is square you only have to do this once. If rectangular, then twice. I learned this method from Sue Nickels. You can also work each corner towards the middle and make adjustments or add motifs there.
Thank You for this lesson Lisa! Happy New Year 🕊