Let me add: another important part of soldering is understanding flux. Most spools of solder are not just lead/tin/etc, they include some chemicals that eat awa

Let me add: another important part of soldering is understanding flux. Most spools of solder are not just lead/tin/etc, they include some chemicals that eat away the oxide layer on metals so that the solder can better adhere. When you solder to a PC board you get a pool of goop around the solder pad; this is the flux. When soldering in the air, it is harder for the flux to go where it needs to go. When soldering wires/leads to each other, it helps to apply flux beforehand, say with a flux pen.