While choosing the right pillow fabric for your space is key, it’s just as important that you choose the right size, pillow insert, and arrangement.

#1 What size pillow inserts should I use?

WHEN ORDERING A PILLOW INSERT, PLEASE CHOOSE A PILLOW INSERT 2″ BIGGER THAN THE PROJECT SIZE SO THAT YOUR CORNERS ARE WELL FILLED. Example: 16″ x 16″ cushion cover should use a 18″ x 18″ pillow form. Measure your pillow insert across the middle of the pillow form. Use a flexible “Tape Measure”, not a ruler to measure your Pillow Insert.
VERY IMPORTANT!!! DO NOT USE A RULER TO MEASURE ANY PILLOW INSERT. ONLY USE A soft tape measure and run it along the middle of the pillow from seam to seam. This is because a pillow is not flat and can not be measured properly with a ruler. For example: you would never use a ruler to measure your waist. The same applies here.

Almost all crafters agree to selecting a pillow insert that is 2″ larger then your pillow cover, such as: Throw Pillows: A Guide to Sizing & Inserts – Francois et Moi