I'd tin the pad, tin the wire, push the wire on the pad, hold a soldering iron on it and wait a few seconds to let the solder flow to make the bond.
Obviously flux everything whilst doing it and clean after with a toothbrush and some IPA.
Soldering temperatures depend on your solder alloy.
If you use leaded solder, you'll need a lower heat to melt it, having it to high will just destroy the iron and or pads/components you're trying to solder.
I'd just stick with the most commonly used temperature appropriate for your solder alloy.