I haven't made mine yet, so this is theoretical.
I know it's important to stay hard, & when you are concentrating at a mechanical task, that's difficult. Consider a helper to focus on technical details so you can focus on being aroused, or a tight cock ring, or a little blue pill.
Shaving will help with clean up, otherwise you're pulling that rubber form out of your hair, or more likely pulling your pubes out with the rubber leakings.
Stand on something disposable, newspaper or such, there's going to be a lot of leakage onto the floor.
I don't know, but i wonder if a vibrator might help settle bubbles in the mold. Air bubbles show up in your finished product, so the less you have the better. Maybe vibrate the liquid mold in the bowl before you pour it into the tube?
I suspect if you use lotion a couple days before that your moist cock may come out of the mold easier. I don't recall if they suggest anything on your cock as you go into the liquid mold.
Decide if you want to go balls in or balls out. Balls in is harder as they want to press the edge of the tube & if they are against the edge, then there is no material, so the final product will have balls with a smooth rounded edge that is unnatural. But your final product will have balls.
Good luck!
