ErgoMechKeyboards

Go for an iron with temperature control and a fine, chisel tip. There are many good brands, Weller is market leader, but cheaper irons can work well too. The chisel tip adds more surface area for more heat conduction.

Flux is very important. No good soldering happens without Flux. Also important to keep a clean tip. I recommend tinning the wire or the contact pad and tinning the iron tip. This should give you enough solder to make the joint without having to hold a piece of solder.

I love Cardas Audio Quad-Enteric solder https://www.cardas.com/supplies Super low melting point makes it great for electronics parts that might be damaged by too much heat.

Pinecil/TS100/TS80p with D-something tips (chisel) are great irons for electronics (and Pinecil > TS***), they are small, temperature controlled, heat up super quick (like seconds) and make using leadfree solder a breeze. Just make sure to also buy a decent power supply with it (if your laptop has a USB-C power supply you can probably use that)

Other than that, practice makes perfect so depending if you're soldering SMD diodes or not consider working on something else first (maybe a kit?), if I can do this then I believe you can too!

If you're just soldering switches, any iron will work just fine.

If you're buying a bare PCB and plan on soldering all the components onto it, you will definitely want a beveled tip.

Louis Rossmann explains why in this video: https://m.youtube.com/watch?v=F05DvDJ4roM&pp=ygUXbG91aXMgcm9zc21hbm4gcmVkIHBpbGw%3D

Buy very thin solder wire. I was struggling until I realized that the wire was too thick. I got thinner wire and everything went smooth.

But cheap practice board for soldered (few USD) and practice first (desolder and solder again after you finish).

If your iron don't have temperature control, but something that has it. I paid around 10usd for mine.

Go with switches first, do controller later, it's slightly more difficult

Just in case it may help: https://lemmy.world/post/3373051