Thanks for that question! I'm going to use a couple of solutions in this thread!

If I can, I sew the vertical sashing between the blocks. I then use one solid piece of sashing on the horizantal sashing strip. If that method won't work, I do the cornerstones in betweeen the blocks/sashing but I also add the triangle pieces (square and sew and flip out) to the sashing so that where the sashing meets the cornerstone it forms a star. You don't notice if they are off a little because of the star effect.

Some really good tips = thanks!

These tips are great!! I will be sashing for the first time on a Quilt for my mom.

Thank you all so much. I'm sitting here wondering, Why didn't I think of that??? I'm sure I'll do better now!

I pin, pin and then pin some more, starting with matching the seams on the blocks and the marks on the sashing where they should match. That helps me to ease in tiny discrepancies that can up to big ones.

re:your 'star effect' in sashing intersections: that sounds intriguing and interest-adding.
Any pictures of that you could show? Would love to see it. I've never sashed before so am interested in any wisdom offered, of which there is indeed much, on this board. Thanks, everyone.

These are good ideas! I usually just pin but have been wanting to try the star at the cornerstone...

I try to put the sashing and cornerstones on the individual blocks whenever possible.

This was the original plan for one of my quilts - a double-nine patch block with star point sashes.

The quilt, the block, the sashing and the cornerstones:

As it turned out, I used so many reds for the stars that it was actually easier to make the stars the main part of the block and make the single 9-patches and plain squares into sashing.

This is the block and the quilt top as it was actually made - it's since been quilted, but I have yet to put the borders on it.