That's the million dollar question. If you make sure that your compass is in good working order, only take off when you have >= 6 sats, and only fly when the sun is calm (http://www.multirotoruk.co.uk/solar-weather), you should be fine.
It sucks, doesn't it.
Run the most recent version of the app and firmware. Those seem to be the least problematic. Buy the Vision Booster app. It helps. When mine drops out, restarting the app usually brings it back. If that doesn't work, restarting the wifi extender usually does the...
I've had mine since mid April and I've flown it 50-60 times and had mostly flawless flights. Every once in a while I get FPV dropouts and I had one VRS-induced hard landing. But that's it. If DJI would fix the compass and the video buffering problems, this thing would be nearly perfect...