How should an agency set up a Performance Max campaign from scratch?
The short answer
A good agency sets up Performance Max in a strict order: conversion tracking first, then the product feed, then the campaign itself. Tracking feeds the algorithm, the feed decides which searches you match, and the campaign settings come last because they only steer what the first two provide. ZenoX follows this sequence on every new account across 200+ ecom brands.
Tracking comes first, always
Performance Max is Smart Bidding end to end. Every decision it makes comes from the conversion data your account sends it. If that data is wrong, missing revenue, or double counting, the campaign optimizes toward a lie, and no setting downstream can repair it.
So the first job on a new account is not the campaign, it is proving that a real sale lands in Google Ads as one conversion with the right revenue attached. That means checking the purchase tag, the revenue values, and whether payment methods like Shop Pay or PayPal report cleanly. An agency that skips straight to building the campaign is building on sand, and you find out a month later when the numbers do not match your bank.
Then the feed, because the feed is the campaign
For an ecom store, Performance Max serves mostly from your Merchant Center feed. Roughly 80% of Shopping results come from the feed, not the bidding, so the feed work is the campaign work. Before launch that means: products approved in Merchant Center, titles rewritten with the main keyword first instead of supplier junk, attributes like color and size filled, honest GTIN handling, and prices that match the site exactly.
This is the step most rushed setups skip, and it is why two agencies launching the same store get different results with identical settings. The one that rebuilt the feed enters more auctions with better matches from day one.
The campaign itself is the easy part
With tracking honest and the feed clean, the campaign is almost simple. One campaign per country, so the algorithm learns each market separately. Real assets in the asset groups: your images, your headlines, not placeholders. Audience signals to point the algorithm at a starting crowd, knowing it will expand beyond them.
The launch settings matter mostly by what you do not do. Do not set a strict target ROAS on day one, because a tight target with zero data strangles delivery before learning starts. Let it run on conversion value first, then introduce a target once steady data exists. And then leave it alone: the learning phase needs days of unbroken data, and every big edit restarts it. The discipline to not touch it is a real part of the setup.
Set up Performance Max from scratch
- 1
Verify conversion tracking end to end
Place a test order and confirm it lands in Google Ads as one conversion with the right revenue. Check Shop Pay and PayPal orders report too. Fix tracking before anything else.
- 2
Get the feed approved and clean
Fix Merchant Center disapprovals, match feed prices to the site exactly, and handle GTINs honestly. A blocked or mismatched feed makes every later step pointless.
- 3
Rewrite the titles that matter
Sort products by expected spend and rewrite titles with the main keyword first, then product type and key details. The feed decides which searches you enter.
- 4
Structure one campaign per country
Each market gets its own campaign so the algorithm learns each country separately. Do not mix markets with different languages and price levels into one.
- 5
Launch without a strict ROAS target
Start on maximize conversion value with no tight target. A strict target ROAS with zero data strangles delivery. Add a target later, once real conversion data exists.
- 6
Leave the learning phase alone
Give the campaign days of unbroken data before judging or editing it. Every big change restarts learning. Review weekly, adjust deliberately, never panic-edit daily.
Related questions
Keep going.
- Should I hire an agency specifically for Performance Max, or can Smart Bidding run itself?
- Does Performance Max beat Standard Shopping for a store that only sells one product?
- Why are my Google Shopping ads not showing?
- How do I optimize my product feed so AI shopping tools actually show my products?
- What is the fastest way to fix low click-through rate on Google Shopping?
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