I'm no expert, I just do what seems to work for me, but the main tip I have for soldering is to prepare as much as possible in advance - tin the ends of wires, tin the lugs on pots and switches.
Then when you're ready to actually put the parts together, do it as quickly and efficently as you can so as not to overheat parts or melt wires. Don't try to "wrap" wires around lugs, just push them into the melted solder, remove the heat, hold for a few seconds and they'll stay in place.
When you're soldering to the back of a pot, it's better to use a really hot iron which will heat the metal - and melt the solder - quickly. If the iron's weak, it'll take ages so the whole pot gets overheated rather than just the little area you want to solder to. It's sometimes worth sanding the back of the pot with some coarse sandpaper so the solder "sticks" better.
Personally, I hold the wire against the pot with the iron as it heats, then push the solder onto the pot under the wire, until just a little melts. Then I keep the iron in place until the solder starts to spread out, like a little pool, across the metal, rather than sitting in a blob. Then I hold the wire down with an old screwdriver or something, take the iron away and hold for a few more seconds to let the solder set. That sounds like it takes ages but it should only be about 30 seconds or so!
