Outside of situations where masking plurality is necessary (e.g. where someone may use known memory problems as an abuse tool), you probably need to mask yourselves less than you think.
Very, very few people will notice overt plurality without being directly told about it. The few that might notice tend to be plural themselves or have plural friends, and they tend to be safe to be spotted by anyway because they're familiar with plurality and how to handle it respectfully.
The average person doesn't have plurality on their radar in the first place. Heck, they barely know what DID is, assuming that they live somewhere it's a diagnosis option, and they've never heard of anything beyond that. Most people will see overt plurality and think "oh, they're moody, or genderfluid, or just use a lot of names, or do a lot of things, or..." if they notice anything different at all.
Seriously, people are oblivious. You can introduce yourself by three different names, have wildly different preferences and modes of expression, and even toss in an accent. The most you might get in response is "are you okay?" (to which the non-disclosure answer is something like "yeah, just feeling different today" or "yeah, I'm just like this sometimes, it's normal". They'll usually let it go if you don't make a fuss about it).
In any case, people are probably not looking for signs of plurality when talking to you- they're more focused on the conversation. The odds of them noticing something different in the first place and bringing it up are low. They have other things to talk about.
