Together with your partner, first think of a concept, that is, a common thread running through the video. The easiest option is, like here, to incorporate the weeks and days into the video. The sex of the baby and some ultrasound images can also be part of the concept.
It is important that it is always located in the same place and in the same context. That makes the video consistent overall. The camera should also always capture the previously defined image section; it is better not to vary the distance. If you want to incorporate larger movements, such as a rotation, break them down into individual steps. Every day then you take a photo with the respective individual step.