Register with a kibbutz volunteer program (see Resources). You will have to fill out an application form and meet a few requirements. For example, you must be no younger than 19 and no older than 35.
Pay the required fees, which will typically include a registration fee, mandatory travel health insurance, and an Israeli visa. These fees vary from program to program, and you can expect to pay approximately $500.
Buy an airline ticket to Ben Gurion Airport in Israel, and arrange for transportation to the kibbutz. Do not buy your ticket before your application has been processed, unless you would like to visit Israel anyway.
