These are my tips about soldering from another thread--you also might want to get some desoldering wick to get rid of excess solder from the join.
A couple of hints for soldering--always have a damp paper towel on hand--it serves many purposes--
Use it to wipe off extra solder from the tip
Use it to drip water to cool a just-soldered connection to cool it fast, or just touch a wet twist to the piece
Use it to cool your finger-thumb-hand after you have paid the Soldering Gods with the obligatory burn
After you finish the piece and are inspecting/fooling around with it, the paper towel will dry out and catch fire to remind you you forgot to unplug the iron.
Also-- put a strong broccoli-type rubber band around the grips of your needle nose pliers to make a gripping tool so you aren't chasing the piece around while trying to solder it.
Wait awhile to be sure the iron is totally hot before starting. Use skinny solder. Consider pre-tinning the piece and the wire to make the final joint faster. You are supposed to make a good mechanical connection before you solder the joint, but that isn't always possible. You may wish to make wires a bit longer and solder outside of your box rather than soldering in place, so you don't melt your box and can remove the circuit later in case you want to change it.