To conduct a PESTLE analysis for retail marketing, you need to research the macro-environmental factors that influence your retail industry, your target market, and your specific business. You can use various sources, such as industry reports, news articles, government policies, and expert opinions. Then, you need to categorize the factors into six groups: political, economic, social, technological, legal, and environmental. You can use a checklist or a diagram to summarize the findings. For each group, you should identify the factors that have the most impact on your retail business, and explain how they affect your opportunities and threats. For example, a political factor could be the trade regulations, an economic factor could be the consumer spending, a social factor could be the lifestyle trends, a technological factor could be the e-commerce platforms, a legal factor could be the consumer protection laws, and an environmental factor could be the sustainability issues.