Vickery retired from the playing side of the sport with a neck injury in 2010 but always stressed his desire to stay involved in the game in one form or another.
"I am really looking forward to the challenge at Cinderford and being part of a professional, proper rugby club," said Vickery, who played all three Tests for the Lions a decade ago before winning a further two caps last time out.
"I have been out of the game for over a year now and this role gives me a chance to get back into rugby, which I love.
"I plan to help the guys develop even further drawing on my experiences and knowledge and provide that extra resource in training to make a difference, plus it will give me a chance to learn so much about the coaching side of the game.
"It's a win-win for both of us really. National One is a high level of rugby and a very competitive national division so it's something to get my teeth into and allows me to be back involved in this great sport."
The World Cup winner and former England skipper will join old Gloucester colleague, personal friend and Cinderford director of rugby Andy Deacon at Dockham Road, starting at tomorrow's game with Birmingham and Solihull.
"Phil has always kept a close eye on Cinderford and shown interest in our progress so when he agreed to join us as a coaching consultant and assist us, I was more than happy," said Deacon.
"He will be a great addition to our resources here and pretty much do what Brian Ashton is doing for Fylde.
"Vicks will boost morale in all areas, plus his experience is second to none. It's impressive too, for our players to be coached by him alongside Lee and Dave. This lays the foundation for a strong second half to the year and a boost to our confidence."