Joining Blocks with Single Crochet
Hold 2 blocks together with the wrong sides facing. Attach white yarn in any corner st (working through both thicknesses.)
Insert hook and draw up a loop.
Ch 1 and sc in the same st. and in each st across until the last corner. End off and weave in the end..
Join the first row in this manner.
Repeat for 2nd and 3rd rows.