Action Details
Requirements and how-to articles for Twitter's action:

paid action
Promote Mode grows your influence by automatically amplifying your message to a larger interested audience.

You need this to get it done:

Twitter Ads Account
A Twitter Ads account is required in order to use Promote Mode.
You can add up to 10 tweets to your Promote Mode campaign each day, with a total of up to 300 tweets per monthly billing period.
Target Audience
You can target your campaign based on up to 5 interests or locations.
Monthly Payment
You will be billed the day you sign up for Promote Mode, then again every 30 days afterwards.
The monthly cost for Promote mode is £79 (GBP) or $99 (USD.)
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How-To Articles
A list of useful links for you:

Twitter Business - Twitter Promote Mode help
Official information on Twitter Promote Mode.
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