The blue tick on Facebook indicates that a user has been verified by Facebook as an authentic account for a public figure, celebrity, or brand. To request verification, you can follow these steps:

1. Ensure that your account meets the eligibility criteria: Facebook requires that your account is active and complete, has a profile picture, and a cover photo. Additionally, you must have been active on Facebook for the past six months, and your account must be in good standing without any violations of Facebook’s rules.
2. Fill out the verification request form: Facebook has a verification request form that you can fill out to request verification. You will need to provide some information about yourself or your brand, including links to your official website, news articles, and other supporting materials.
3. Wait for Facebook to review your request: Facebook will review your request and notify you whether your account has been verified or not. The verification process can take several weeks or even months, so be patient and keep checking your email for updates.

Note that the verification process is not guaranteed, and Facebook may deny your request even if you meet all the eligibility criteria. Facebook may also revoke verification if your account no longer meets the eligibility criteria or if you violate Facebook’s rules.