Start by drawing out your initial cutting board design with a pencil, so you can use it as a guide. I didn't follow my drawings precisely when I started cutting. But it was nice to see the drawing, so I had an idea of the shape I wanted to create.

Next, clamp your piece of wood down to the table or another sturdy surface, so the wood doesn't move around while cutting.

Then, using a jigsaw, carefully cut out the design you drew on the board in step one. I typically go slow with the jigsaw, so I can see where I'm cutting and it helps with precision too.

Once the cutting is done, use a sander to sand every surface of the finished board (including the sides). You can also sand by hand, but it will take longer. A small detail sander is great for curved areas that are hard to get to with a larger sander. It's also good for smoothing the interior areas of any handles you create, that would otherwise be difficult to get to for smoothing.

Once all the sanding is complete, wipe the board of any debris and use a cloth to evenly wipe the oil over the entire board - front, back, and sides. Let the oil sink in and repeat the process if necessary. Most of the things that I've read about oiling say to do two coats, so that's what I would recommend. Then, it's ready to use.