With the same thread start a second ring with 16ds. Join to second picot of the underlying chain going through your previous ring (image step 6).
Then work the other part of the ring and close (image step 7)
Take your work to the other side and load the 4mm bead on the thread of the other color (image step 8).
Reduce gap and with the same thread start a ring: 3ds, join to picot of first big ring, 3-3-3 and close (image step 9).
Work other two rings: 3+3-3-3, and 3+3-6 (image step 10)
Lock join to the 4mm bead (image step 11)