@jaz_rose I'd say you need to practice your bf and fb knots so they are more consistent, make sure you are not pulling the bracelet to either side while knotting and also making sure you always do 2 bf or fb knots if it's an alpha (in a normal it's just one).
@mireblue I recommend watching MashaKnots' video in the flat alpha technique. You can also read the tutorial on alphabet patterns by @Adik. The tutorial explains how you can do two-coloured alphas which is a technique you can use for the pattern you mentioned.