Christian occasions
Baptisms, christenings, first communions and confirmations share a pattern: a service that guests must arrive on time for, followed by a gathering somewhere else.
That second location is the detail most often missed, so it deserves its own line. A working example: EMMA'S BAPTISM: Sun May 10, service 11am at St Mark's, lunch afterwards at 22 Ellis Road.
For guests who do not attend church regularly, saying whether they should arrive early and where to sit removes a real anxiety and improves attendance.
Muslim occasions
Iftar gatherings during Ramadan turn on timing, since the meal begins at sunset and the time shifts a little each evening. Naming the actual time rather than saying at sunset saves every guest looking it up.
Eid gatherings often follow prayers, so guests need to know whether they are invited to the prayer, the meal, or both, and where each takes place.
An aqiqah, a nikah or a milad each carry their own expectations. Stating clearly what the gathering is lets guests who are unfamiliar with it prepare properly rather than guessing.
Hindu occasions
A puja at home, a Diwali gathering, a housewarming or a naming ceremony all bring together family and neighbours who may not share the tradition.
The two details worth including are the timing, which is often set by an auspicious window rather than convenience, and whether food will be served and when. Guests plan around both.
For a longer ceremony, telling guests they may arrive during a particular period rather than at a fixed moment is kinder than leaving them to work it out.
Writing an invitation for guests outside the tradition
The most useful thing you can do for a guest unfamiliar with the occasion is answer the questions they will not ask: how long it lasts, what to wear, whether food is served, and whether they should bring anything.
One extra sentence covers most of it. Ceremony lasts about an hour, please dress modestly, dinner follows tells a guest everything they need without a phone call.
Because you only have about 160 characters, the practical details of what to expect are often better as a second message closer to the day. Scheduling that follow-up means writing it once and forgetting it.
Guest lists that cross several circles
These occasions gather people from places that do not overlap: family, the congregation, work colleagues, neighbours. No single group chat reaches all of them.
Sharing one sign-up link into each circle solves that, and everyone lands in the same list without you assembling anything by hand.
Private one-to-one messages also matter here, since a guest list mixing family and neighbours is not one you would want visible to everyone on it. For ongoing community communication rather than a one-off occasion, texting a congregation covers that separately.