I've used a gaiwan for years, but I still don't quite have the hang of it. I feel much more comfortable with a teeny yixing pot and a cup.
At least one of the three criteria (tea/water ratio, water temperature, and brew time) is a no brainer- the water should be just off the boil, no thermometer necessary.
As for the other two parameters, you'll have to play around. Make sure you use enough leaf and start with very short steeps, and take it from there. Sometimes five seconds is too long, and other times sixty seconds isn't enough.
I never bought a sample, as I think a cake is a sample.
Chief Weasel and Director of the B&B Stjynnkii Membörd Dummpsjterd.
Baby Brain Smooth.
Life is too short to share that bacon with anyone.