In feet, how big is your coop? Your run? Photos showing how the two tie together and showing the layout inside your coop could be helpful. To me, room is very important in this and it's just easier to give specific suggestions if I know what you are working with. With just six chickens I'm concerned your facilities may be pretty small. One way chickens have learned to live together is when there is conflict the weaker runs away from the strong and then avoids them. That's why room is so important, they need room to run away and get away, and room to avoid if there is conflict.
I pretty much agree with Rosemarythyme. House them across wire for a week or so and see how it goes. Give them as much room as you can and improve the quality of what room you have with clutter. Separate food and water stations, preferably out of line of sight of each other are good. As a minimum I'd do food and water in the coop and food and water in the run so they are separated. When I do this I have either three or four feed stations and four or five water stations, depending on whether I'm using my grow-out coop or not.
So I’ve noticed that about 98% of the videos on YouTube on adding to the flock goes from look but not touch to placing them in the coop on the roosts at night and the next day they are just one happy flock…. Does this really work or is there a good bit of editing done to these videos?
I use a version of that, but with a couple of huge differences. I do not lock them in the coop with the others at night until they have
proven to me that they can coexist without violence when intermingling in the coop and run during the day. With my logistics the chicks are usually around 12 weeks old when they go in the coop and have been intermingling for about a month.
I don't try to put them on the roosts with the others, I just toss them on the coop floor, lock the door, and let them figure it out. Mine are highly unlikely to sleep on the roosts with the adults anyway so they find their own comfortable place to sleep. I don't care where they sleep as long as it is predator proof and not in my nests. I do this so often that I put up a juvenile roost lower than the main roosts, horizontally separated from the adult roosts, and higher than the nests. A lot of the time they sleep on the floor for a while, but when they are ready to roost there is a safe place to go that is not my nests.
I think it helps that I have a lot of room, over 3,000 square feet outside and an 8' x 12' coop. They can hide under my nests if they are frightened and they often are. When I go down in the morning to let them out the younger ones are usually on the roosts with the adults on the floor. My roosts are high enough that the adults can't peck them from the coop floor. Not everybody's roosts are that high.
We make this sound horrible, it's usually not that bad, especially if you have some room. I have the room and facilities that I can take it very slow. I make an effort to not force them to work things out immediately but give them time to work them out on their schedule. Sometimes you can just put them together with no "see but don't touch" without problems during the day, it doesn't have to be at night. Again, the more room you have the more likely that is to work.
My suggestion knowing nothing about your facilities is to try it during the day when you can be around to observe and make your decisions based on what you see. If you try locking them in the coop at night, be out there at daybreak when they are waking up to see how it is going. If you consider your run predator proof you don't have to leave that door locked closed so they can get outside at wakeup without you being there.
Good luck with it, it is usually not as hard as we make it sound. But do observe, it can be a disaster.
