Hi Vince. Specopwhat? lol. No such training. Not difficult to make one...just very very time consuming. I picked up the netting and jute string on Ebay. There are plans that come with many of the "ghillie kits". I winged it and made a more versatile (I hope) version of the "pancho" version. You can also find lots of info on making these suits on "google" or YouTube.
I made this one more like a netting or wrap. It's a jagged bottomed/edged 6' x 9' wrap/sheet. I DID NOT cut out arms or hood. I just left the net mainly intact....so Ican use it for a pancho as pictured, or as just a blind or covering depending on the situation and terrain. I took a camo boonie (floppy) hat and tied some fish netting onto the hat with the camo colored jute string...then strung up the netting with lots of colored jute string. My "suit" is a 2 parter...hat and cape/pancho/sheet. I also have a pair of camo pants with the "ghillie flaps" that I can wear underneath.
The suit is pretty heavy...about 6-7 lbs I believe. It is surprisingly cool considering it looks like a wookie. :D Lots of open holes in the netting to let air pass. Still not something I'd like to wear on the desert. Most of the kits you can choose the color of jute string to suit your needs. I put a lot of tan in the suit to keep it cooler in the Florida sun. Not to mention we have a lot of dead folage during the dry winter months...which is breeding season for most of the birds.
Good luck making one. It's boring tedius work...and took too many hours, but I'm hoping it pays high profits with some good shots of difficult birds.
Even just the hat/hood is a handy thing to have. You never know when a costume party will break out and you need an 80's Tina Turner costume. :-)