Williams was one of only two Welshmen selected for the Lions this year along with forward Jac Morgan.
He said the experience of his first tour was “pretty surreal”.
“I don’t mean to sound disrespectful to my teams, but the quality around you, there’s world-class players everywhere,” he said.
“Boys just make jobs easier for boys around them – the training standard and the skill level in training was pretty decent.
“That was kind of cool to be a part of.”
With a new responsibility at club level this season, Williams said he hopes the time he spent in the Lions set-up will add more to his game when he returns to the pitch.
“There’s a lot of voices in those kind of environments, but a lot of good voices as well. If I think back I’m pretty sure I could take a few pointers from a lot of the boys,” he added.
Williams takes over the captain’s armband at Gloucester from Lewis Ludlow, who held it for the past five seasons.
Director of rugby George Skivington took Williams for dinner to ask him to take on the role which he said was an “easy decision” and a “real honour”.
“I couldn’t say no to that. I don’t think it’s anything you can turn down,” he said.
