In Seller Central, go to Advertising and click ‘Create Campaign’. Next select the product/s that you want to advertise, set the daily budget for advertising spend, and how long you want the ad campaign to run for. Lastly, you must choose the keyword targeting type you want to use: manual or automatic. Manual targeting is where you pre-select the keywords that you want to target. Automatic targeting is where Amazon will select keywords for you based on what similar products are targeting.