My final piece of advice is to follow a checklist before every flight. Here's the one I use:
Day Before Flight:
- Charge flight and remote control batteries
- Check for drone firmware updates
- Confirm memory card contents are loaded to computer, format and test
- Check weather forecast for planned time and location
- Verify planned location does not have any flight restrictions in place
Day of Flight
- Check drone compass calibration at location
- Verify GPS lock, battery status, and memory card before takeoff
- Visually inspect aircraft and propellers; look for any cracks in plastic or other potential issues
- Ensure phone is fully charged before takeoff
- Confirm manual controls functioning properly immediately after takeoff
Those are the basic steps I recommend performing before every flight. You may find that you want to customize the list a bit. For instance, if you use filters, make sure you have the right ones, or if you have a drone with support for interchangeable lenses, make sure you have the right lenses with you.