How to refill PGI250/CLI251 - PIXMA MG 2420/5420/5520/5522/5620/6320/6420/6620/7120/7520

PIXMA MG 2420/5420/5520/5522/5620/6320/6420/6620/7120/7520 PIXMA MX 722/922 PIXMA iP 7220/8720 PIXMA iX 6820 Auto Ink Refiller