We are considering here to add donation button. In order to add Paypal button in wordpress blog one need perform below mentioned steps:
1) Login into Paypal.com. If one has no account at Paypal then sign up for free service.
2) Click on Merchant services.
3) Click on websites payment standards.
4) Click on accept contributions.
5) Click on get donation button.
6) Now one can configure their donation button and provide require details like…donation name, service, Donation ID, Number, Amount of Donation, currency etc..,
6) Choose the button style from the provided list.
7) One must have to set Button Encryption to No in order to generate the code for wordpress blog.
8) Click on create button now.
9) One can get code for websites and Link for details.
10) Go to your WordPress.com dashboard -> Write -> Post or Write -> Page wherever you would like to place your button but make sure you are in HTML view.
11) Save the changes.