I've noticed a couple of different people saying their soldering skills aren't that good. Well you don't have to be an expert to accomplish a good solder job. All you need are some basics so I thought I'd see if I could help out.
The solder iron:
You don't need to spend a lot of money on a soldering iron. I think I paid about $20us for this model. There are basically two types, irons and guns. Although a gun heats up much faster than an iron, I would recommend an iron over a gun simply because they are easier to control in cramped spaces. A stand and a sponge are a must! The stand, of course, keeps you from burning things up, while the sponge is used to keep your tip clean. This stand actually has a helping hands, but I removed it for the pic. If you are not familiar with the helping hands, all they are is a couple of alligator clips on articulated arms. They come in very handy when you are trying to solder two wires or small parts.
Something you want to look for is some kind of temperature control. This iron has a 15 watt and 30 watt setting. The lower wattage is great for things like circuit boards while the higher setting is used for soldering two or more wires together.
This is the business end of the iron. The screw allows you to replace the tip as they do eventually burn out. You can also install different sizes and types of tip as well, although, I personally have never had a use for a larger tip or say a chisel point type tip. Your uses may include one of these so don't be afraid to experiment.
Get a heat sink!
One more thing you will want in your tool box is a heat sink. This is a small clamp that you attach between the component you are soldering and the solder joint. This helps dissipate heat so you don't burn up the LED's you just purchased.
On to the soldering
Let's start with the solder. I all most exclusively use a .022 diameter solder. It melts fast and I don't get a big unexpected glob on my joint. In a lot of soldering tut's you might read how important clean wires are, how important flux is (flux is simply a cleaner) but if you are using freshly stripped wire, new components, etc...it's not really all that important because most modern solder contains a center core of flux or rosin. You do have to be careful as some wires do have a coating on them, but that is easily scraped off. After stripping your wire the first thing to do is "tin" the end. Tinning is simply impregnating a small amount of solder into the wire. To do this, as with any joint, you apply your heat to one side of the wire and the solder to the other side. The idea is to heat the wire to melt the solder and not melt the solder with the iron.
The finished tin job. This will make to much easier to make the connection and is especially important when soldering to a circuit board.
When connecting two wires this is the best type of connection. Not only does this help hold the wires together while you are soldering but it also gives you the best electrical contact area. Again to complete this joint apply heat to one side and your solder to the other. Don't forget to slip on your shrink wrap before completing the joint.
When soldering LED's, resistors, capacitors and other components you should use a heat sink. This will keep the component from getting to hot, and in the case of an LED, keep the plastic surrounding it from melting. Simply clip the heat sink between the component and the joint you are about to solder keeping the heat sink as close to the joint as possible.
Circuit Boards
When soldering on a circuit board I recommend using the lower heat setting on you iron. This will help prevent "lifting" of the copper etching of the board. It is pretty easy to ruin your board if you get it to hot. The heat one side, solder on the other technique still applies here though. You want the solder to flow around the wire not just glob it on.
Summing up
There are two kind of joints you can end up with when soldering, a hot joint or a cold joint. The kind you want is the hot joint. It will look shiny and smooth and will conduct electricity. A cold joint will be dull looking and not conduct electricity well. A cold joint occurs when the wire or joint is not heated to the melting point of the solder. A cold joint is easy to fix, simply reheat the connection until the solder flows easily. If you are in doubt about your connection simply get out you volt/ohm meter (you do have one don't you?) and check the circuit for continuity.
One aspect of soldering I have not covered here is "desoldering". Maybe you made the wrong connection or you want to remove a component from an an old circuit board but it is something you will at one time or another have to do. There are several desoldering tools that available. The most popular being the tube type. This is a metal tube with a spring loaded plunger. You cock the plunger, heat your joint, then use the vacuum created by the plunger to suck out the old solder. Personally I prefer to use whats called solder wick. This is a braided wire that pulls the melted solder from the joint. I find it much easier to use than the tube type.
I hope this shows you that soldering is not rocket science and any one can accomplish it. All it takes is the right tools and a little patience. Practice on some spare wire and some old boards then start your project.
It's easier than you think!