the math part:
add 7/8" to the desired finished size of your hst block.
example: 3" finished hst block will start with 3 7/8" squares.
{to make 3 1/2" unfinished hst block.}
the making part:
cut two squares of fabric...one light, one dark.
yall will cut these according to your desired finished hst block size.
draw a line on the wrong side of your light square of fabric.
with right sides together, stitch 1/4" seam on both sides of your drawn line.
cut apart on your drawn line.
press to your darkest fabric.
trim your dog ears and you're done.
this will give yall 2 hst blocks.
for those inquiring minds:
fabrics are simple abundance by bonnie and camille for moda.