Ryan told the Evening Times: "Whenever you go away you have to make sure that you give the opposition nothing for free.
"Scarlets have a lot of strong runners and none more so than George North, so we are also going to have to be defensively very sound.
"But they have a lot to play for, as do we, they are still very much in the play-off mix and with this one being at their place and at this stage of the season they will see it as a must-win game.
"Scarlets like to run the ball through the hands and get it out wide so, if it is good in terms of weather, then I think we will see a very attacking contest.
"It is going to be a tough day at the office but we are ready for it.
"But I think we are in a very good place right now. We know that our destiny is in our hands and that is the way it must stay at full-time on Friday night."
Scarlets already have a win over the Warriors this season - an 18-13 victory at Scotstoun back in September.
But with Glasgow sitting top of the pile with just three games left of the regulation campaign the tough prop is eager to reverse that result.
Ryan said: "Yeah, they came to Scotstoun on our opening night and really gate-crashed the party and it was very frustrating.
"We hadn't really got going back then as it was only the second game of the campaign and we definitely owe them one for it.
"But we have lost just one out of our last nine league games and we have tremendous momentum with us and we are heading to Wales with confidence high we can put that defeat right."