A good and persuasive landing page holds its position in the campaign planning as this is the first milestone for every business who are trying to gain the attention of customers. The landing page should be compelling enough to draw their interest, so that they would end up fulfilling your goal.
Design
This is the first thing that will have a huge impact on the effectiveness of landing page to drive conversions.

Smart use of color

Eye-catching images

Colored buttons

Elements size
To The Point Content
The content should only contain necessary information needed to encourage them to convert.

Highlight Key Info with Bullet points

Scannable Font Size and Alignments

Clean and Clear Visuals
Headers
Headings and sub-headings help in providing a key opportunity to promote the theme of the landing page. Here you can impress the visitors with just one line and make them your customers.

Bold and Subtle Message

Clear and convincing
Credibility
Now that you have gained the attention of users, you need to give more trust signals to increase the probability of the conversion. Consider following options:

Testmonials

Social Media Share options

Trust Badges

Mention Coalitions
Mobile Friendly
Nearly 52% of world’s population are mobile internet users. Making your landing page mobile responsive is very important if you want to come in good books of users and search engine as well. You must check following options for it:

Easy Navigation

Fast Loading

Clickable Elements

Font and Alignment
Brief Forms
Whether the goal of landing page is to collect info or not, but you got to collect as much data as you can from them. Always try to get only required details as asking for much information may decrease the chances of getting the forms filled. Consider following points:

Highlight the Subject in headings

Keep the form fields precise

Don’t ask for personal info

Include a Thank You message on completion
Landing Page as per the Audience
The
landing page must be tailored as the audience you are targeting. If the audience are directing from search engines or some newsletter link, then they will be quite different from those coming from social media platforms. You need to differentiate your audience between B2B & B2C or Formal & Casual.
Similar Content Flow from Ad to Landing Page
The language should be same, and the key phrases should match the words used in campaigns as this will reassure the visitors that they are on the right path. There should not be any gap between the messages. It is important that users are directly delivered to the content they are looking for. Connect the flow to exact desired destination to make the conversions happen.
Testing
This is the most important phase as with this you will get to know the efficiency of the landing page. Perform extensive testing via different testing modules like:

A/B Testing

Multivariate Testing

Split Testing
Final Execution
With the test case analysis, improvise the landing page to cover the loose ends and launch the landing page. Opt different targeting methods to gain attention like:

PPC

Newsletters

Remarketing to old customers

Outreach