I recently addressed the importance of including hashtags in your tweets. Every tweet, when it comes to news, should have at least one.

Now the tough part: how do you pick your hashtags?

The Next Web recently wrote about hashtags and gave this example of what not to do:

There seems to be a misguided assumption among some Twitterers that in order for their tweet to show up in searches it needs to be filled with hashtags. It’s not uncommon to see these people write things like “I just tried to use #iPhone #Tweetdeck but it kept #crashing. Back to #Tweetie I go”.

It’s not necessary to write your tweets like this because (1) that’s too many hashtags, making it hard to read, (2) the hashtags are poorly chosen, and (3) this is not a newsworthy tweet.

The best way to pick hashtags is to see what other people are using as hashtags about the same or a similar topic. That way, your tweets can be indexed alongside theirs. For example, many people were using “#crisishn” for the Honduras crisis recently, and you may not have known this unless you’re checking other people’s tweets or searching Twitter.

#crisishn is an example of an event hashtag. Another example is #iranelection. Anything related, about Honduras or Iran, should include these hashtags because it groups them together and makes them easier to find.

Then there are location hashtags. If you’re writing something newsworthy, it’s good to provide a geographical location like #nyc (or #newyork), #uk (or #england), or #asia, depending on the story focus and whether it’s local, regional, national, or continental.

There are also topical hashtags. These are terms like #earthquake or #journ for journalism. They’re good to know, especially when you’re searching for information.

And finally, there are name hashtags. When President Barack Obama is giving an important speech, #Obama may be used. Sometimes #Ahmadinejad, #Merkel and other foreign leaders appear as hashtags in themselves. Brand names like #Apple or #Microsoft could also be considered name hashtags.

In general, if you have a breaking news tweet, you should include at least one hashtag. Many times, it goes at the end of your tweet and it won’t repeat a word you’ve already used. The event hashtag is preferred (which may also include a conference or seminar hashtag), probably second would be the location hashtag, followed by the topical hashtag, and finally the name hashtag.

Don’t put too many hashtags in your tweets, but put enough to make it easy for your reader to see what you’re talking about, and easier for people going through hundreds of tweets to spot yours in search (and to group them with related tweets).