Goto your Blogger Template> Edit HTML and expand the widget templates..Now find
<p class='post-footer-line post-footer-line-3'/>
and immediately after that place the text from this file after properly editing it with your paypal email address(replace youremailaddress with the email address using which you registered at paypal)..
If you have any doubts leave a comment.. and if you like the trick then why not buy me a coffee from that link below!!??