The best way to promote a landing page with a CPA offer is through paid advertising. You can use platforms like Google Ads and Facebook Ads for targeted traffic. These platforms allow you to reach specific audiences who are interested in your offer. You need to create compelling ads that encourage users to click. Social media marketing is also a great option for promotion. You should ensure that your landing page is mobile-friendly and loads quickly. Email campaigns can drive more visitors to your landing page. Testing and tracking your results will help you improve performance of your CPA campaign offer. You should only focus on quality traffic for better conversions.