Cut 3 lengths of green cord measuring approx. 35". You may want to use a little less for a shorter necklace, but this can be altered at the end.
Cut 2 lengths of pearl cord measuring the same length.

Thread on a cream rondelle ring bead, a green extra large bead, a cream extra large bead, a green extra large bead and another cream rondelle ring bead. 
Position these in the centre of the cords. 

Thread on 4 or 5 of the small rondelle beads onto the individual cords.
Repeat on the other side of the necklace with 4 or 5 more beads.
Alternate between 8x10mm and 10x12mm.

Losely weave these cords on each side so that the cords mix together. There is no pattern to follow.
Repeat this on the other side so that the cords hold the beads at different heights on the necklace.
Add a drop of glue to the cord where you want the beads to 'float'/ sit on the cords and move the bead so that it covers the glue and is secured in place. 

Knot each end of the necklace.
Create an overhand knot on one side of the necklace.
Before pulling the knot tight, pass the other side of the necklace through it.
Close the knot.
This should mean that one side of the necklace can slide through the knot.