One step. Then check.
Break every feature into steps you can test on their own. Build one, check it works, commit it, then ask for the next.
The page, with dummy content
STEP 1 · CHECK · COMMIT
Layout
Fields that accept input
STEP 2 · CHECK · COMMIT
Form
Entries stored somewhere
STEP 3 · CHECK · COMMIT
Save
Saved entries shown back
STEP 4 · CHECK · COMMIT
List
An email when one is added
STEP 5 · CHECK · COMMIT
Notify
Small steps, checked often, committed each time.