A scant quarter-inch is generally recommended across the board for quilting patterns. There are a couple ways to achieve this. If your sewing machine has a quarter-inch foot, you can use this to get an accurate seam allowance for quilting. Your foot may also have a metal ridge to mark a precise quarter inch.
An alternate method is to place a piece of masking tape or a sticky note on the base of your sewing machine to mark the correct distance away from the right edge of your foot..
Pressing your seams after each step can also help with piecing accuracy. Be sure to press your iron up and down instead of waving it from side to side, which can stretch or distort your fabric and make straight seams look wonky.