I like to set FD limit screws with the FD cable disconnected I shift between rings with my left hand while turning the crank with my right. Set the inner limit so that it won't shift to the small cog, then back it out just until it shifts. Then check to see if the chain rubs in the small ring/large cog combination. If it rubs back the screw out until it no longer rubs. On the large ring, turn the limit screw in until the chain rubs while in the large ring/small cog combination, then back it out until rubbing stops. Next check to be sure it will shift from middle to large ring. If not, back the limit screw out until it will shift. Once limit screws are right you can connect the cable. You will want the cable to be pretty tight initially, but not so tight that it moves off the limit screw. I set the cable adjuster fairly short initially but still leaving a turn or two to decrease tension, in case I pulled the cable too tight to start.