Head over to the Style section and click on the Add Block in the position you'd like to add your text. For example, if you want to add it at the top of your profile, tap on the first button; if instead you want it after the profile picture, you can tap on the second button. See example below:
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In the new modal window that opens, select Donation/Thanks Box as shown below:
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Finally, complete the required data with your PayPal email address, as shown below:
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