The Safety Note on Loss of Directional Control while Landing contains information from the NTSB database indicating a high landing incident rate during Phase One test flying. I gave a lot of thought about how to reduce risk while I was test flying and gaining experience on my Bearhawk. The main take-away item from the NTSB records is that nearly all accidents during the Phase One test flying period are a result of "Loss of directional control while landing".
Considerations for initial test flying
Become very current on a taildragger.
If at all possible, get some instruction on a Bearhawk from a Bearhawk instructor.
Initially, use only grass runways that are into wind where possible.
The first 3 points above should largely eliminate most "loss of directional control" accidents on landing.
Use the brakes only when necessary.
Fly the local circuit in another aircraft to become thoroughly familiar with the circuit pattern on the same runway as first flight is intended to be flown from.
Keep the fuel tanks at least half full at all times. This reduces the risk of inadvertently un-porting a fuel line while proving the fuel system, and while becoming accustomed to flying the Bearhawk consistently in balance.
Fill the fuel tanks to the top at each refuel and log the quantity you put into each tank. If you find that it takes different amounts to fill each tank it may be because the aircraft is being flown out of balance.
Perform a very thorough preflight each time.
Where possible, keep the flights over flat ground (plenty of landing options).
After initial test flying is complete
Establish the position error between IAS and TAS.
Practice crosswind takeoffs and landings.
Begin practicing a "tail low wheeler".
Begin practicing normal STOL approach technique (if desired), and consistently landing on the aim point.
After the test flying was complete and the C of A was issued, I started venturing into the backcountry with other pilots. Flying with others who were more experienced in the backcountry was a very good way to learn. I also flew quite a number of hours in another Bearhawk, operating into some tight airstrips and gravel bars.
Some quick rules of thumb to help get started in the backcountry
Fly light to reduce approach speed and landing distance. 2 POB and 3 hours fuel is a rough rule of thumb. 2200lbs works well on my 4-place Bearhawk. Take the fuel you need, plus a sensible margin (rather than filling the tanks to the top).
Practice on a large grass runway with displaced threshold first - much better to make mistakes where there is plenty of room for error and recovery.
Land using a "tail low wheeler" landing (and take-off) - much less stress on the airframe by keeping the tailwheel off the ground. Visibility is greatly improved.
Fly with others who can show you the ropes and get a briefing from them first.
Keep the CG mid to forward to improve ground handling and reduce potential for a ground loop.
Fly in good weather - light winds and good visibility. Less chance of turbulence or strong tail-winds, and you'll be able to concentrate on what you need to.
Fly initially into airstrips at a low density altitude. This keeps your groundspeed lower on approach and landing.
Make up a survival kit and leave it in the aircraft.
Consider communications. A flat tire or flat battery can leave you stranded and out of mobile phone coverage. A Garmin InReach Mini or similar can enable a text message via satellite for help. They mount well on a bicycle handle bar mount on the overhead cross-tubes in the Bearhawk cockpit.
Google earth is a great resource for studying an approach and doing a "flyover" to become familiar with landmarks and lining up on airstrips that are difficult to see.
Stabilized approach - always. This means having profile, speed and flap configured appropriately.
Wind - check the wind and groundspeed on the EFIS display when getting close to an airstrip, and also on approach. If you're uncomfortable with it, go-around while you still can.