Looks good so far! Keep it up. Don't be discouraged if you make a lure and it totally is a flop. We have all been there. Just give it a try, don't overthink your first lures.
The tough part of a diving crankbait is getting the lip slot to be perpendicular to the wood so it dives true. I like to cut that slip slot while i have flat sides. You will have to kind eyeball where to put the lip. At this point I would take some 80 or 120 grit or so and sand it to the shape you like it. Maybe finish off with 220 or so. Then cut the lip slot/put wire in and weight (it will most likely need a bit of weight to give it a ballast). Once all the hardware is in, I would seal the wood one way or another. It helps keep any moisture out, but really it can help the overall appearance of your lure. There are tons of methods - polycrylic, polyurethane, superglue, epoxy are a few.
Size and shape of the diving lip will be tricky to if you want to make a unique lure. Honestly, copy one of your favorites to start. It will give you a feel for how it works. Then you can start making the same kinda lure and try different size or shapes or angles, there are many options. You can learn a lot from the ones you fail at too!
There is tons to talk about - keep asking questions.