One last important thing I forgot to mention is to constantly wipe your soldering tip with paper or the soldering cleaner sponge.

Make sure that every time you solder those pins, the tip has to be as clean as possible.

melted the lead onto the tip with a small portion, just a little that barely anything on the tip, too much will cause over soldering, so you need to be sure you put as little as possible and build it up slowly and do not rush

Some Lead wire cause the black burn so pick the thinest lead wire.

May the force be with you.