You can use any wire you have. Large diameter wire will be more difficult to manipulate, but will increase the rigidity of the product You can combine colors and beads sizes as you like.

materials I used : beads : 4mm, 6mm (abacus crystal) Soft copper wire 22 gauge ( wire diameter 0.6mm ) : 2 pieces of 6cm ( 2.5 inch) for each link 1.5cm ( 0.6 inch) for basic link You can use them ...