To make more interesting patterns all you have to do is take out and up or down strums. With the next example the 1st half beat and the 2nd half beat are not included in with the strum pattern. When you strum on the 1st & 2nd half beat, you miss the strings and don't make a sound. When you miss a string you still have to strum up so you can get ready for the next down strum. Download the video example so you can see how the strum is played, or you can play the mp3 example to listen to the audio only.
The Diagram below is the same pattern as what is above except it repeats endlessly. Remember to say the word "Miss" when you strum, but don't make a sound when strumming. You can practice strumming along with the animated diagram until you get it correct. Also use the audio mp3 example to help you with the sound. To remember the pattern say "Down Miss Down Miss Down Up Down Up". When you start strumming a new pattern, you should say it like this so that the words you say reinforce what your arm is strumming. It is more difficult to strum down when you're saying the word up.