A Youtube viewer writes:
I’ve never used a double edge razor, just the disposal 2,3,4 and 5 blade varieties. Before I invest in a quality DE razor would it be useful to practice my technique using a disposable single blade razor like a bic?
You can certainly try a disposable like the Bic–considering the price you don’t have anything to lose–but in my opinion its not really close enough for practicing DE technique. They’re way too light, the blades aren’t as sharp as they could be, and the razor head geometry is completely different. I’ve found that a two blade razor like a Sensor XL or Atra (if you can find one) is a lot closer.
Or you can ask old friends/relatives if they have a vintage Gillette laying around the bathroom you could have.