If the sky is not cloudy at 5:29PM Today I'll snap a picture of the Northwest Horizon ... Where according to http://www.heavens-above.com I will be able to see the International Space Station just above the horizon.
Here is the web page for ISSwave "http://www.isswave.org/" Here is how you do it:
 Go to http://www.heavens-above.com and enter your latitude/longitude and click on the link that will find when and where from your location the International Space Station will be visible.
 Send a "tweet" in the following format: "[your message] #ISSwave [your zip code] US" leave out the double quotes and replace the [stuff] with your stuff.
Once you do the 'tweet' your 'wave' will show up on the isswave.org web site map.
If you live outside the united states you can still do this. If you do not have a 'twitter' account you can still do this by sending the isswave.org site an email message.
And you can use other sites than heavens-above.com to figure out when and where to look for the International Space Station in your area.
Here is a graphic of the details of the pass for my location (this afternoon).
Well it was cloudy - But - I still went to the Shelly Lake Dam and waved in the direction that the ISS would have been visible if there had been no cloud cover, and here is a graphic of my wave (I do have twitter so I could send the tweet):