In case you have two sections' letter paper pieces both sections.
Sew together the sections.
Then add two pieces on the left and right.
Then add pieces up and down.
Then align the paper hexagon on the back and reduce the exceed fabric.
As the hexagon has lines you can easily align them to the stitch lines.
Make EPP your prefered way.
I pin and baste.
If it is still difficult to center the hexagon to the letter, look at the following tricks.