The keystone skill for an electronics tinkerer is soldering (and, of course, its dark twin, desoldering). This section will also discuss using a multimeter, building circuits, and troubleshooting projects.
Figure A-18 shows good and bad soldered joints. In general, good soldering requires four steps, illustrated in Figure A-19 and Figure A-20: make a mechanical connection, apply heat, apply solder, then cool and trim.
If your soldering iron has a brand new tip, you should tin the tip before using it. Plug in the iron, and when the tip is nice and hot, melt some fresh solder onto it to coat the tip and prevent corrosion (which will otherwise eat away the tip pretty quickly).
Figure A-18. Good (left) and absurdly bad (right) solder ...