The devil is in the details. Here is what I would recommend:
If it's a new pattern to you, do a trial block to verify your seam allowance, pressing order, and overall size.
Do not use flimsy fabric.
Test your fabric for color fastness and prewash if necessary.
Cut accurately.
Sew a consistent seam.
Press so the seams nest (if possible).
Square up the block.
Measure the top across the center and cut straight borders to that length. Then ease in any difference. (This will keep you from having wavy borders.)
Most importantly, have fun and ask lots of questions in the forums. We are always glad to share our quiltiness.
