Step 1: Be quiet
Don't say anything, even when spoken to. Someone asks how you are? Don't say anything. Someone asks if you're ready? Don't say anything. Someone asks if you want that shiny new piece of gear? You guessed it, don't say anything.
If you must interact with the person use simple emotes. /nod /ready /no
You can also roll on things occasionally. But really, since this is the Silent Bob approach, you should be fine with your black coat like chest piece and the demon slaying golf club. George Carlin for the win, am I right?
Step 2: Always stand next to the hyper guy
By standing next to the hyper guy (the one who always talks and jumps around a lot) you'll barely have to talk or interact with the group. No matter if it's at the summoning stone, in a city, or during a boss fight, always stand next to him. He'll do 99% of the talking for you.
For example, someone in the party asks "Can I get a summons?" If you were alone at the summoning stone, away from hyper guy, you'd have to answer "yes." But since you're next to hyper guy at the summoning stone, he'll answer "Snootch to the bootch! Hell yes, me and Silent Bob are here to summon you! Natch!" You've avoided having to say anything and are proving yourself a worthy member of the group.
And if you're away from the summoning stone with the hyper guy? Then you're babysitting him so the group will get started quickly. Thus, you're still proving yourself a worthy member of the group.
Step 3: Speak once, and only once
Those who are students of Kevin Smith can tell you that in each of his Askewniverse movies Silent Bob essentially speaks once and only once. And when Silent Bob does speak, it is profound and life changing for the subject of his communication. Holden needs a kick in the pants? Silent Bob tells him how he's chasing Amy. Dante needs to appreciate his girlfriend? Silent Bob's remarks on lasagna clarify the situation. Poop monster got you down? Silent Bob is the instrument of He who is I am.
Take this approach in the group you're in. Pick one critical moment when everything is going wrong and speak then. Not only will everyone actually listen to what you're saying, chances are everyone will actually do what you say.
Three steps. Almost no talking. And you know what?