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

You need this to get it done:

Budget and Payment Method
Set either a daily or total budget for your Snap Ad campaign, and set a payment method (credit card or PayPal.) You can also set a goal (video views or impressions) and bid type (auto bid or max bid.)
Business Account
A Snapchat Business Account is required in order to use the Snap Ads Manager.
Brand Name
The brand name which will appear in the upper left corner of your Snap Ad (must match the paying Advertiser whose products or services are being advertised) (maximum of 25 characters including spaces.)
File format: .mp4/.mov
Video length: 3 - 6 seconds
Aspect ratio: 9:16
Resolution: 1080 x 1920 pixels
Maximum file size: 32MB
Encoding: h.264
It is recommended to have a 150 pixel buffer at the top and bottom of the canvas where no logos or other graphic elements are placed.
Video Audio (required)
Channels: 2 (left and right) (balanced throughout)
Target level: -16 LUFS
Encoding: .pcm/.aac
Minimum bitrate: 192 Kbps
Sample rate: 48 KHz
Set how long you would like your ad to run for (you can either set start and end times or have it run indefinitely until you decide to pause it.)
Business Address
The address associated with your business (street address, city, state/province and zip/postal code.)
The headline which will appear in the upper left corner of your Snap Ad (maximum of 34 characters including spaces.)
Target Audience
Choose your target audience based on location, age, gender and interests.
The name for your Snap Ad which will show up in your creative library, reports and notifications.
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How-To Articles
A list of useful links for you:

Snapchat Business Center - Commercial Specifications
Official Commercial specs, restrictions and creative recommendations.
Link missing here or found errors? Improve How-Tos