Always include a direct link. Every reminder should include a clickable RSVP link. Do not ask guests to go find the original invitation. If they have to search, they will not do it.
Include the date in every reminder. People should not have to click the link just to remember when the event is. Put the date front and center so they can check their calendar immediately.
Make declining easy. Explicitly say that a decline helps you plan. Many people avoid responding because they feel bad saying no. Give them permission.
Use the channel they prefer. If someone lives on WhatsApp, texting them an email-style reminder will not land. Match the channel to the person.
Set a clear RSVP deadline. Deadlines create urgency. Without one, responding to your invitation stays permanently on their to-do list — which means it never gets done. Use a
QR code on printed materials so guests can respond the moment they see it.