This is a guest post from Rob Hillyard at Return on Digital . Create a brand new campaign for Remarketing. This will enable you to monitor how everything is doing much easier than running it within an existing campaign. You need at least 500 people in your target list before Google will start to show your ads. Depending on how much traffic your site gets and who you are targeting, it could take a couple of days before you see any traffic. Image ads work best.