These are the tips to optimize your landing page:-

1. Out Bound Link

2. Call To Action

3. Conversion

4. Trust

5. Search Intent

6. Remarketing Code

7. Facebook Pixel

8. Google Analytics

9. Conversion Tracking Code

10. Font & Color

11. Simplicity 

12. A/B Testing

13. Heatmap

14. Email List Building

15. Optimize your landing page for SEO

16. Social Media Icon

etc....