This is how i learned to strum:
I was taught the basic pattern " Down Down, Up Up, Down Up. I used this very much, and as time passed i began alternating it in order to make it sound nice in other songs etc. In other words; I figured how other patterns where played by listening to trhe rythm - just needed a little push from the basic pattern i mentioned up there.
Point is that i think you can do the same thing, because best way to learn this is to use your ears.
Ofcourse those basic pattern on that page is a very good start, but it really comes down to using your side attachments - simplest way.
(A) (C#) (D-barrè) (Cm#)(Bm)
Stand by your guitar, and tell the world you love it!