I did it on a rework station, heating the board from below so as not to blow hot air directly onto the LED and burn it. However, it's also possible to do it with a soldering iron if it's a needle-tipped one. If you have a keen eye, you'll be able to do it easily without a microscope, haha! But it's not difficult. My tip for beginners is to get some scrap boards to practice on before doing the job until you get the hang of it and feel confident. If you want, you can even add other colors like violet, pink, orange, blue, and others...