I assume you will be getting sexed chicks mailed to you from a hatchery of getting sexed chicks from a feed store. In either case, chicks just a few days old. Then you want to integrate them with your flock. We do this all of the time but there are different methods used.
No matter the method, the more room you can give them the better. In these posts my first questions are usually how much room do you have in the coop? How much room in the run? How do they tie together? Photos can be helpful.
I'll assume you want to add 6 to 8 chicks to your existing 6 hens.
What will the daytime highs and the nighttime lows be when you integrate them?
Until my pullets reach laying age I essentially have two sub-flocks. The juveniles avoid the adults during the day and also do not roost on the same roosts at night. Some people seem to think that them being integrated means they are hanging out together, sharing food and water, and cuddling. That's not reality. Until they start to lay my integration goal is that they are not hurting each other. All that one big happy flock comes after they start to lay.
You can brood them in your house or some other area away from the coop and integrate them into your flock when they are old enough to be able to handle the temperatures without heating them. I don't do it that way but many do. There are a lot of threads on here about housing them across wire for a week or two and then slowly letting them mingle.
My brooder is in the coop. Mine go straight there from the incubator or from the post office. I keep them in that brooder for five weeks, then open the brooder door and walk away. It is that easy. But...., there is always a but. How much room will yours have?
My adults spend all day every day outside when I'm doing this. When a hen goes inside to lay an egg she ignores the chicks if they are in the coop. I have over 2,000 square feet outside. Withing 2 or 3 days of opening the brooder door the chicks leave the coop each morning and spend all day outside. They have plenty of room to avoid the adults. I have several feeding and watering stations. They can eat and drink without being bullied by the adults. If the adults approach them the chicks quickly run away.
At dark they all go into the coop to sleep. The adults go to the roosts while the chicks find another place to sleep. As long as it is not in my nests and is someplace predator safe I don't care where they sleep. When I open the pop door every morning to let them out the adults are typically on the coop floor while the chicks are safely out of reach on the roosts. My roosts are high enough so that is a safe place from adults on the coop floor.
I find the hardest thing about brooding outside instead of in a climate-controlled area are the temperature swings. Mine can go from freezing to into the 70's Fahrenheit in a day. Until they are feathered out and can handle the temperatures without heat, they need a spot that is warm enough in the coldest temperatures and a spot that is cool enough in the warmest temperatures. I accomplish that by have a big brooder where I can keep one corner warm but have enough ventilation so the far end can cool off to ambient temperatures.
With sufficient room and decent weather this does not have to be that hard. With temperature extremes (hot or cold) and limited space it can be more challenging, but there are techniques to deal with those if we know what you are working with.
Good luck!
