I’ll speak to a few things from E’s perspective. Ultimately you will have a better time of it if E does better, so as much as you feel you have to protect yourselves against E— investing effort to help E feel protected from the world where feasible can be a more proactive measure.
Consider known irritants and distractions and see if you can eliminate, soften or mask them. In my experience noise from inside and outside the home can be very distracting and can lead to added thought processing and reality-checking. When you have psychosis and delusions you are constantly in a state of alert, similar to feelings you have when you hear a noise in the night and you lay awake imagining it’s a burglar or wild animal. It’s a fight or flight mechanism, and can lead to escalating delusional explanations. It can be helpful to give E some control over the environment, some examples are drapes or white noise machines.
Unless E is a hoarding type who is comforted by collections of possessions, consider decluttering the home. Suicide is sometimes a risk after hospitalization, so removing any weapons and other high risk items that could be repurposed for self-harm is a good idea. I advise against playing radio or televisions for long periods of time and consider limiting Internet use if possible. If you keep a lot of food on-hand, especially sweets or junk food, consider giving surplus food to a food bank. Many antipsychotic drugs increase appetite and having loads of food in the house can be extremely tempting, and constant snacking and overeating may result if food access is uncontrolled.
Mental wards are often time-structured and regimented for good reason— it controls stimulation and adds discipline. Consider setting a schedule and help E stick to it. Try to have E wake, bathe, eat, sleep at fixed times. Mental wards also have ‘activities’ which encourage social interaction and stimulating physical and mental activities. Card and board games are good for this, as are social walking and calisthenics, interaction and care for animals, mealtime preparation and conversation, cooperative chores, running errands outside the home, etc. If E is musically inclined or interested in arts or crafts it can be therapeutic to encourage these by getting work materials before E returns.
If E smokes or drinks alcohol or stimulants like coffee or tea, consider rules and logistics for these like ashtrays, designated smoking areas etc. People with SZ and other SMI tend to self-medicate for various reasons. Many people with SZ tend to smoke or drink coffee compulsively, in my case I drank coffee to counteract sedating effects of medication. Drugs and alcohol are sometimes used to escape or distract from symptoms, but these are rarely helpful and often exacerbate conditions.