Soldering is an easy skill to learn, but it can also be easy to mess up when you're working on really small items. To give yourself a little more control, you can turn a mechanical pencil into a simple precision dispenser.
Instructables user MoTinkerGNome demonstrates that it's as easy as it sounds in his guide. Get some 0.5mm solder and a .5mm mechanical pencil and you're most of the way there. Remove the eraser, empty all the graphite out of the pencil, and carefully thread the solder into the pencil. Give it a few clicks and the pencil will start to push the solder through the end. This gives you a lot of control and helps prevent kinks and bends in the solder line. Check out the complete guide at the link below.
0.5mm Precision Solder Pencil... or Got Lead? [Instructables]