Take more pictures and videos than you think you should. Document everything, especially the mundane. You will never regret taking a video or photo. I have a 16 year old and time flies so fast, but we look back at the past with fondness. My wife and I were smugly talking (to each other, never brag to other parents) about how our son didn’t have tantrums, until I found a video of him having one. You are so sleep deprived that you will forget a lot, but you can rely on the video evidence