Well, considering I have DID it's hard for me to remember all of the things we did /j
We're still not perfect, but better than we were a few years ago when we started to figure out what DID even actually was. Needless to say, we were pretty surprised to figure out that DID was the perfect label for our experiences that up until then, were just messy, confusing and weird. That was pretty much our starting point... so, congrats on step One!
Some of the more simple things that helped us in the long run was logging switches (we're almost ALWAYS on Discord, so we use PluralKit)
Giving our alters more room to actually be themselves was also really helpful. Letting them open up about their names, aesthetics, even just existences. I never knew that 🩸 was an alter, just me being SO angry that I'd lose control of my body. Turns out they were a persecutor. Giving them their own name and letting them address their own boundaries was a great starting point for the relationship we have now. They don't LOVE me in the simplest way of the word, but that's how they want to be, and I think letting them be how they want without shaming or fearing them has resulted in them being a lot more "agreeable" for a lack of better word.
Pluralkit especially makes it easy to set up profiles that can differentiate everyone in a personalized way, but I think too if you choose to have a physical journal, you could still find a way to personalize that too. Maybe have a section of the journal dedicated to information on each alter, and use different colors and decorations to make it more Them. OFC that's just a silly suggestion :P
Communication will look different for each alter I've come to accept; maybe it's different for others but that's at least where we're at. Me and 🪲 can carry full on conversations in my head, whereas me and 🐰 are barely even capable of comfortably co-fronting. Communicating with 🩸 to me is just acknowledging that they're there, and giving them the choice to leave their "cage" or stay exactly where they are. The cage's door used to always be locked shut, but we've let it stay open... so to speak. They choose to stay in it, but the door is always open if they decide that they want to come out.
Understanding that just even Generally Speaking your emotions aren't a bad thing, and are there for a reason, is the best way to foster a healthy environment with each other.
Anger is scary, sure, but it's there for a reason, and you have a right to be angry. It's a human emotion we all have. And if you have an alter who is angry, that's alright. They're angry for a reason, and usually it's because they're hurt. Exercising compassion to alters is a wonderful way to start practicing compassion to yourself as a whole, and when you learn to open up with yourself like that and start to fear yourself less, the doors in your system just seem to open up on their own in a way.