At an early startup, the release checklist often lives in a founder's head. That works until there are enough changes, or enough people, that nobody can hold it all. Your first browser suite doesn't need to be big. It needs to be small enough that every failure gets looked at.
Write the checklist down
List what you check before you ship: signing in, the main action your product exists for, whatever customers pay for. You'll probably find some of it was never written anywhere.
Choose depth before breadth
One test with stable data and a meaningful outcome is a better starting point than many vague click-throughs. Pick a repeatable sign-in, search or account flow, set up its test data and write an explicit assertion. Review its failures before you add more.
Product priorities move quickly at this stage, and a large suite can outgrow the team's capacity to review it. Expand when the team can explain the existing results and has a clear reason for the next flow.
Don't gate anything too early
You don't need CI on day one. Run saved tests before a release, and add a merge gate when a merge workflow would actually help and someone owns the failures. A blocking suite nobody owns just gets bypassed.
Don't chase a coverage percentage either, or automate a requirement that's still changing every week.
With Zerocheck
Paste the checklist into the web app, run the drafts with test accounts, sort out anything unclear and save the useful tests. There's no local install for hosted testing. The optional CLI adds repository YAML, localhost runs and use in an existing CI job.
It's US$500 a month, with US$500 in credits at sign up, a dedicated instance and hands-on setup of your first tests.