As you continue to pull out the jib with the jibsheet, enough of the sail will soon be exposed to catch the wind. Be sure to keep tension on the furling line to prevent the jib from rushing out all at once and flailing in the wind.
Also keep tension on the jibsheet so that the sail keeps better shape. Usually it is necessary to put the jibsheet on a winch, once the sail catches the wind, and to start cranking the winch to bring in the sheet as the sail unfurls. Ideally, try to keep the jib in trim for your point of sail as it unrolls.
When the jib is all the way out, cleat the furling line and trim the jib using its telltales.
In windy conditions, you may not want the jib fully unrolled. You can reef the jib by leaving a few wraps of the jib still furled.