The data subject (the person whose data you want to process) must provide an explicit statement of consent. The obvious way to do this is with a written statement from the data subject. To avoid any doubt, you can also have it signed by the data subject. But this is not the only way you can obtain explicit consent.
Online statement
In a digital or online context, a data subject can provide the required statement by filling out an electronic form, sending an e-mail, uploading a scanned document with a signature, or signing electronically.
Website
You can also offer visitors to your website a screen where they can give their explicit consent by clicking "Yes" or "No.
Note that the text here must clearly articulate the consent. For example, "I hereby consent to the processing of my data.
Of course, in doing so, you must also provide enough information to your visitors about what you will do with their data if they give permission.
Oral statement
In theory, an oral statement may also be sufficient, but in doing so, it may be difficult for you to prove that you have met all the conditions for valid express consent.
Learn more
For more information, see the AVG guidelines on consent, Chapter 4.