Sign up to several CPA networks. Find out which landing pages convert the best. Option A ) Some affiliate networks will actually display the conversion rate for each campaign / landing page. Option B) You may need to talk with your affiliate manager to find out which landing pages convert the best. Collect the top 5 - 10 landing pages. Modify each one for your niche and campaign. Option A) Outsource this work. Option B) Download Photoshop and do it yourself. Split test and modify accordingly.