QuiltE

As already said ...... squaring up is not an end thing, but a before you begin thing!

To me the fabric preparation is as important as every step along the way.
Then precision cutting of the pieces.
Precision stitching and checking at each stage.
Pressing after every seam is vital (not ironing and stretching).
For example, is that 6-1/2" completed block, really 6-1/2" all around the block?
If not, best to fix the problem now, before making 49 of those!
And so on .... til you put on the borders.
Ditto to borders a bit wider, to allow you some trimming room at the end.

Quilt as desired, staying within the final seam/binding edge,
so that your quilt design shows when complete.

Then a long stitch around the outer edge, holding all layers of the sandwich together.
For the final trimming and squaring, a nice large table to work on.
I usually find a common seam and measure out 8" or WHY, and then trim,
making sure the corners are squared/right angles.

Alas ........ the crowning glory. The binding!
Precision again with even stitching/seamline all round.
Good cornering methods so they can be nice and sharp and pointy!
After the machine stitching and before the hand stitching starts,
I then stitch close to the edge of the inside of the binding seam to
holds it all nicely together to give a crisp edge to the finished binding.
Again, careful hand stitching (ladder stitch) and cornering
to ensure that crowning glory, is just that!

Sounds like a lot of work and attention, but not really.
Whether a quilt for my bed, or an every day placemat, or one for charity,
I figure they all deserve the best efforts, I can give.

It really is worth it!!