In this thread, we will be going through wheel stud replacement. Firstly, How do you know you need to replace a wheel stud? The answer is simple... whenever one or more becomes stripped or loose. If you see either of things starting to happen, replace immediately!
For starters, you will need to read through The Front Brake Rotor Replacement Thread
as the disassembling of the hub is described in detail there. Once accustomed with that process, we can move on to the simple act of replacing the studs!
Knocking out the old studs. A simple process... With the hub down, and the studs facing up, hammer the old ones out! They will simply slide out the back side of the hub. Some force may be needed!
Get the new studs, and with the back side of the hub facing up, slide them into place. Once again, hammer them into place. Some force will be needed here as well, but be more careful when installing, you don't want the new ones getting loose again.
Once they are all in, the hub can be reassembled (wheel bearings packed etc.)