Step 1: Prepare diaper and materials
It is important to assemble your materials so that everything is in arms reach from the start, because the faster you're able to perform the diaper change, the less likely you are to get peed on.
Cloth diapers come in different weaves, weights and sizes. If you are buying your own set of cloth diapers to wash and wear (more power to you!), it might be good to know that the flat rectangular diapers that are shown in the following instructable are called "prefolds" (not to be confused with the diapers that actually look prefolded like a disposable--those are called "all-in-ones"--or flatfolds, which are not yet folded). Prefolds are folded and stitched so that there is a triple thickness of cloth down the center of the diaper. If you use a diaper service (I use Tiny Tots in the Bay Area), your diapers are probably made of heavyweight twill. Try to make sure the diapers you are using are for the approximate age/weight range of the baby, or you will face frustration.
Diaper covers come in lots of varieties as well, but most of them have a waterproof lining on the inside that keeps the cloth diaper (which is very effective at wicking liquid!) from wetting the baby's clothes. These, too, come in different sizes for different size babies--check to make sure you're in the ball-park on size.
Finally, there are lots of ways to secure cloth diapers so that they stay on the baby. In this Instructable we use Snappi fasteners. Snappis are a stretchy "Y" band of plastic with little teeth that dig into the diaper fabric and hold everything in place. These are really convenient to use--you can put them on with one hand while the other holds the diaper in place. You can buy these from Amazon, if you can't find them anywhere else.