To start using Pinterest ads for e-commerce, you need to create a business account and claim your website. This will give you access to the Pinterest Ads Manager, where you can create and manage campaigns, track performance, and analyze analytics. Additionally, claiming your website will enable you to use rich pins that show extra information from your website. You should also install the Pinterest tag on your website. This code helps measure user actions taken after seeing your ads and create remarketing audiences. Then, choose a campaign objective and budget, based on your goal. You can also set a daily or lifetime budget, as well as a bid strategy such as cost per click (CPC), cost per impression (CPM), or cost per action (CPA). When creating an ad group, target your audience based on demographics, interests, keywords, or behaviors. You can also use custom or actalike audiences from your own data. Finally, design an ad creative with vertical aspect ratios, bright colors, clear text, and compelling calls to action. Also make sure that the landing page matches the ad creative, offers a clear value proposition, and has a smooth checkout process.