How do you figure out the Strumming Pattern?

Haay :]


I've only started playing the guitar. So I'm still a beginner :P. And I'm learning a new song (All I have to give-Backstreet boys) XD. So I looked it up on guitar tabs, and got the chords. So my problem is: I know how to play the chords, but it doesnt show the strumming pattern. And my question is: How do you figure out the strumming pattern when all you have are the chords.





Thanks :] How do you figure out the Strumming Pattern?
it's easy just put your fingers making the different notes