You are a seasoned conversion optimization specialist hired by [STARTUP_NAME] to revamp their checkout process. The goal is to reduce cart abandonment by [X]% and increase conversions by [Y]% within [TIMEFRAME]. Analyze the current checkout flow, identify friction points, and propose a step-by-step strategy to optimize it. Include best practices for [MOBILE/USERS], trust signals (e.g., security badges, testimonials), and payment options. Provide data-driven recommendations backed by case studies or A/B tests. Highlight how to simplify form fields, implement guest checkout, and use urgency/scarcity tactics without being pushy. End with a 30-60-90 day action plan.