I passed my verification test on the 1-hour flight home from the airport where it was installed. I also did not have a nearby Class C or Class B airspace to use, so here is what I did:
Start engine
Turn on avionics
Ensure transponder is squawking 1200 and in Alt mode
Wait for GPS to fully start up and get a position fix (our GNS 430W is the position source for the new GTX 335 transponder)
Taxi no more than 20 knots ground speed
Take off, turn outbound, and climb at best rate up to 10,500 (I also watched ForeFlight to be sure I was above 10,000 by GPS and the transponder to be sure it was reporting a pressure altitude over 10,000 before I started watching the clock at all)
Level off at 10,500 and start a timer
After 5 minutes, do a standard-rate 360-degree right turn, then proceed on course
After 5 minutes, climb at best rate to 12,500 and level off
After 5 minutes, do a standard-rate 360-degree left turn, then proceed on course
After 5 minutes, start a 500 fpm descent to 10,500, but when reaching 12,000 start a standard-rate 360-degree right turn, rolling wings level around 11,000 if you did it right, then continue the descent on course to 10,500 and level off
After 5 minutes, verify that total time above 10,000 MSL by all three measurements (indicated, GPS, and pressure as squawked by the transponder) is over 30 minutes
Perform a steady 500 fpm descent to pattern altitude at destination airport, enter the pattern on downwind, fly a standard pattern
Land and come to a complete stop on the runway centerline
Wait a few seconds
Turn around and taxi to the ramp at no more than 20 knots ground speed
Come to a complete stop on the ramp for a few seconds
Turn off avionics
Shut down engine
You are supposed to do 30 minutes of "maneuvering flight" in rule airspace. I probably went overboard with multiple turns, a climb, and a descent that included a descending turn, but I did pass on the first try so my method at least has that going for it. Your mileage may vary and the most common failure is apparently the ground vs. flight determination made by the transponder. Good luck!