Here's a 2022-era guide on much better quality DIY video stabilization:
- Capture the gyro and accelerometer data along with your video (slap a smartphone on your camera if it doesn't have its own sensors)
- Feed both video and sensor data to gyroflow [1], synchronize and stabilize it.
The sensor-based stabilization is easy and looks uncannily good compared to pure software stabilization which is typically hit-and-miss. A good 3 axis gimbal is still better as it also compensates for parallax, but for deshaking the results are really similar.