If you have time to knit, if you've taken up knitting, it means you're not worried about the essential stuff. --- Stephanie Pearl-Mcphee

This video was recorded during a live stream on Periscope. You may hear me talking to someone. I am able to read peoples comments as I stream. Part two is below.

The things you will need to properly block a granny square.

A craft blocking board. (They are available at Michaels, Amazon as well as your local yarn store.)
T-pins
Spray bottle
lavender essential oil is optional

I like to add two drops of lavender essential oil to my spray bottle, so when I spray the granny squares, they are lightly protected by moths. My great grandmother always did this and then redid after every washing. She never used moth balls and I still have all her crochet work. I store her zillions of doilies in acid free paper in a cedar chest. It helps to keep the yarn from yellowing and being eaten by pesky moths.

Granny Square blocking

Line up one corner to the edge of one grid.
Pin it on an angle.
Line up the edge along the line of the grid.
Pin the next corner.
Continue all the way around and then when all 4 corners are secure. Mist the fabric lightly with cool water. Allow to dry overnight. Then unpin to easy sew together into a blanket or jacket.

Knit garment pieces work the same way. And yes it is worth the time to block all your pieces before sewing them together.