Using this Hakko soldering tip is easy. First, make sure your FX - 888 soldering iron is turned off and cooled down. Then, swap out the old tip with the new T18 - S4 tip in just 30 seconds. When you start soldering, set the iron to the appropriate temperature according to whether you're using lead or lead - free solder. For lead solder, a common temperature is around 350°C, and for lead - free, it's usually 370 - 400°C. While soldering, keep the tip clean to ensure good heat transfer. After use, turn off the iron and let it cool. Once it's cooled, wipe the tip gently with a damp sponge to remove any residue. Store the iron in a dry place to prevent rusting. Also, avoid applying too much pressure when soldering, as it can damage the tip and the circuit board.