Step 2
Pass the left thread end through the last threaded B so that the thread ends cross in this bead and the beads sit in the middle of the thread piece. Pull tight.
The thread end that points towards the centre of the flower we call thread end Y.
The thread end that lies on the outer edge of the flower we call thread end Z.
(For simplicity: since the thread ends constantly "swap" when crossing, simply orient yourself by the shape: inside = Y, outside = Z.)