What are some design best practices for an effective landing page?

1:They are super focused on the marketing theme. 

2:They Keep Scrolling to a Minimum

3:They are relevant to the message of the campaign.

4:Engaging, keeping the interest with a view to offer solutions

5:Effective visual, relate-able visuals and and full of them 

6:Consistent Branding through out the campaign

7:They have a specific CTA, 

There are a lot of good articles out there, have a read of  landing page examples from Unbounce.