Introductions are much more complicated than just putting the cages near each other. You need to go through some time swapping pouches and toys so they get used to each other's scents, then actually spend some time supervising them together in a neutral territory. A cage is NEVER a good place to do an initial intro, you will inevitably have one glider invading the others' space, and you also won't be able to break up a fight very well if once should occur. There are some much more extensive articles on intros in the gliderpedia that you should read.
Creating a colony takes no more than doing careful introductions and paying close attention to personalities. Some groups of gliders can live well together, others can not. If you are talking about making a colony from the joeys of your current pairing, you will not need to worry about intros, you will just have to get your neuters done in a timely fashion. Other than that, I'm not really sure what type of set up you are talking about. If you are meaning colony BREEDING, that's a WHOLE other can of worms that is extremely complicated and risky.