The link is not the whole handover. The message around the link teaches the client how to enter the experience, what to do first, and what to expect after opening the stack.
Open with context
Start with one personal sentence about the shoot. It does not need to be long. The point is to make the delivery feel intentional, not automated.
Explain favourites
If you need selections, say so clearly. Ask the client to tap the heart icon on the photos they love, then submit the favourites list when they are done. Do not assume they know the workflow.
Explain downloads
If downloads are enabled, tell them where to find the download option and what size to choose. If downloads are locked until payment, say that before they discover it on their own.
Include a deadline
If the stack expires, mention the date. It protects your storage and gives the client a clear reason to save what they need on time.