radial roots

I'm still learning the techniques of the art of bonsai. Between here, YouTube and the rest of the net, I can sometimes get the rough idea. So I'm wondering here on how is it possible to grow surface roots to this level of purrfection other than photoshop. I'm not seeing any signs of wounds...

I have a 10 month old ficus benghalensis as well as a 10 month old ficus religiosa. I'm trying to work on developing their radial roots and wanted to know if the shape of the pot matters (round vs rectangular vs square)? I'm assuming round is best for developing even radial roots?

As I began learning more about bonsai, I stumbled across a concept you guys are all very familiar with, but was new to me: Air-Pruning. I learned about it while researching a local tree nursery that uses "The Rootmaker System" by reading the literature on their website. Pictured below is an...

I collected this American Elm last spring, and it’s done really well since. I checked out the roots this spring and there was a clump of roots on one side and a few little roots on the other - I sorted the roots as well as I could and buried it deep. I didn’t have any sphagnum moss so it’s just...