After you have all of your photo transfers ironed onto your white squares, you are ready to start assembling your squares.  Take one of your white squares and center it on one of your colored squares.  Using straight pins, pin your whit square to your colored square.  Sew your white square onto your colored square.   Sew about 1/4 of an inch from the edge of the photo.  Trim any white material away from your square after you have it sewn onto your colored square.  Do this to all of your white squares, remembering to alternate between your two colors of squares.

You can now take some trim of some sort and sew it on top of your stitch line from before,after pinning it in place.   Adjusting it as needed to not cover up your photo.  Any kind of trim will work.  I have used one inch eyelet lace, narrow ribbon about a quarter of an inch wide, and even rickrack.  Which ever looks best to you.  Remember to use the same color of thread as your trim, so your stitch line won’t be so noticable.   If you decide against using a trim that is ok too.  You may want to fold and pin your white square under at the edges before you sew it on so there will be no raw edges on your white square.  Next sewing your colored squares together.