As with any job, there's usually more than one way to do it. Instead of learning a specific technique, it's better to understand the principles behind the task, so you can problem solve when things don't work out. Resawing is the same way. You learn one method only to find out it doesn't work today on this piece of wood with this particular blade. Having a couple of techniques and understanding the principles of resawing will give you options during different circumstances.
The following methods assume a well-tuned saw, proper blade selection and a certain amount of skill. I highly suggest practicing these methods on scrap wood rather than on something you're depending on for a finished project. For further reading I recommend Mark Duginske's Bandsaw Handbook (200393).
The most obvious approach is free hand resawing. Flatten one side of a board, join an adjacent edge and mark continuously around all four edges with a gauge referenced from the flatten side. With the joined edge on the saw's table, feed the board into the blade making minute adjustments as you go. Speed is the advantage here. No fences to set up, no lead angles to calculate, just mark and go. Let the blade cut the way it wants. If you have a dull blade and can't get a new one in time, you can sometimes get away with free handing a board. You thus avoid the compressed, C-shaped surfaces dull blades produce. Free hand resawing becomes the only choice for some woods that are case hardened, suffering from compression, or that have some other defect. These defects cause wood to distort while being sawn, and can bind against a fence, knocking the work off line.
Free hand resawing makes sense if you only have a couple of boards to do. An example would be book matching, which produces only two pieces from one board. Because it requires a great deal of muscle control and skill, it's not the best choice if you're new to the bandsaw or if you need to produce a stack of veneers.
A point fence is nothing more than some 3/4" stock rounded on the end and clamped perpendicular to the blade. The point fence lets you bear against something solid while you feed your stock into the blade. By following your layout line, you account for blade drift with less muscle control than with the free hand method. It offers more predictability while retaining some of the simplicity of free hand resawing. You still have to make minute adjustments as you work, but it's less fatiguing and more reliable. Point fence resawing is a good choice if you have more than a few book matches, or when free hand resawing is too risky.
If you want to take multiple passes on a single board with a point fence, you'll have to unclamp and move the fence for each rip. This way the flat side is always against the fence and the joined edge is always on the table. In any case you should sight down the work board at each pass to insure the piece hasn't warped.
A bandsaw fence resembles any fence we're familiar with like a tablesaw fence for instance. Unlike a tablesaw fence, which must be parallel to the blade, a bandsaw fence must be able to skew to allow for blade drift. Blade drift is also called lead angle, and is a fact of life. Sometimes it can be as much as a few degrees left or right of the blade, and occasionally it is unperceivable.
The first step is to determine which way your saw wants to cut today. Join a board and mark a line parallel to that joined edge. Now, free hand rip that board on the marked line at a good pace, and turn off the saw when you are half way through the rip. Inevitably the board will be skewed in relation to the blade either to the left or right. Draw a line on the saw table using the joined edge as a guide. Take a sliding bevel and set it to the drawn angle on the table. Use the bevel to set your straight fence for the lead angle. Take a test cut and readjust if necessary.
Different manufacturers have different ways to adjust their fences for lead angle. Some don't allow for adjustment, so you'll have to modify the fence or improvise. Of course you could make your own out of plywood or MDF and hold it down with C-clamps. Kreg makes an aftermarket Bandsaw Fence (124023) that fits most saws, and it's fairly easy to skew. You can also get a Kreg 4-1/2" Curved Resaw Guide (124025) or a Kreg 7" Curved Resaw Guide (124026). These fences act like point fences and readily attach to the Kreg Bandsaw Fence.
The straight fence method is probably the technique of choice in a production setting like when making veneers. It's very predictable once you've set everything up, and requires the least physical effort to control the work piece. You only have to flatten and join once and keep those surfaces registered to the fence and the table respectively. You then move the fence closer to the blade after each rip. The piece falls off to the right presuming the saw's frame post is on your left. But straight fence resawing assumes the wood is well behaved and won't warp, twist or bow as is comes off the saw. As the blade dulls and its geometry changes, you may have to reset the fence to a new lead angle.
So there you have it; three ways to resaw wood on a bandsaw. Learn each one so you'll have options when things don't go well. Above all, practice and analyze what's going on. You'll find yourself getting less frustrated and enjoying the woodworking process even more.