How to get free World Book Day tokens?

I'm curious to know, how does one acquire free World Book Day tokens? Are there specific events or promotions I should be looking out for? Is there a limit to the number of tokens one can obtain? And, how can I ensure that I don't miss out on these opportunities? As a book lover, I'm excited about the prospect of getting my hands on some of these tokens to enjoy free books. Could you please elaborate on the process and any tips you might have to help me secure them?