How can I optimize my Amazon PPC campaigns to improve their performance ?

Amazon PPC campaigns are completely unpredictable, and even a few little flaws can have a huge impact on your performance. However, a fully optimized PPC campaign will significantly increase your sales for a surprisingly modest price. You can improve the performance by below steps
1.Analyze your competitors
2.Benefit from automation
3.Construct Structured Campaigns
4.At Least Once a Week, Optimize

You can optimize your Amazon PPC campaigns by negative targeting of irrelevant keywords and ASINs and changing bidding strategies, by applying placements and adding new keywords.

One simple tactic is to understand your customer behavior, check when they majorly purchase the product and at what time they only window shop, so keep your budget for that time at the minimum and run your campaigns fully during the peak sale time, the rest of the basic things such as negative targeting, bid adjustment extra can be done one daily and weekly basis respectively.

You have to control irrelevant clicks that cause bleeding, do negative targeting, optimize your main image, and work on reviews.