Staging points work like Outpost warping. Specific places in Aht Urhgan where you can warp to get to places easier, most likely used for Experience/ ffxi powerleveling Merit Parties but some missions require you to go to those or near spots so they are very handy to have.

 To get access to the runic portals you first need to go to the Staging Point you want or need and usually talk to a NPC Imperial (looks like a Blue Mage) and then use the runic portal to warp back to White Gate.

 Then you will have access to it. Ok let's cheap ffxi gil get the easy one ou cheap final fantasy gil t of cheap gil final fantasy xi the way: